Biology Dictionary: A
Search or browse the dictionary for the definition of biology terms starting with the letter “A”.
Dictionary > A
A
- A
- A Band
- A chain
- A granules
- A layer
- A posteriori
- A priori
- A-v
- A1-acid glycoprotein
- Abandon
- Abbreviations
- Abdomen
- Abdominal cavity
- Abdominal raphe
- Abdominopelvic cavity
- Abdominopelvic splanchnic nerves
- Abduction
- Aberrant
- Aberrant regeneration
- Aberration
- Abhorrent
- Abilities
- Ability
- Abiogenesis
- Abiotic
- Abiotic factor
- Abiotic factors
- Abiotic Fixation
- Abiotic resource
- Abiotic stress
- Ablation
- Ablutomania
- Abnormal
- Abnormality
- Abo blood group
- Abolish
- Aboral
- Abortion
- Abortive transduction
- Abp
- Abrams heart reflex
- Abrasion
- Abrasive
- Abscisic acid
- Abscissa
- Abscission
- Absence
- Absent
- Absolute fitness
- Absolute Refractory Period
- Absolution
- Absorbance
- Absorbent
- Absorption cell
- Absorption chromatography
- Absorption Spectrum
- Absorptive cells of intestine
- Abstinence
- Abstract
- Abstraction
- Abundance
- Abundant
- Abuse
- Abyss
- Abyssal
- Acanthion
- Acaulescent
- Accelerate
- Acceleration
- Acceleration phase
- Accelerator nerves
- Accelerin
- Accent
- Accentuation
- Acceptor
- Access
- Accessible
- Accession
- Accessories
- Accessory
- Accessory Chromosome
- Accessory fruit
- Accessory organs
- Accessory pancreatic duct
- Accessory pigment
- Accessory symptom
- Accident
- Accidental host
- Acclimation
- Acclimatization
- Accole forms
- Accommodation
- Accommodation reflex
- Accounting
- Accretion
- Accretions
- Accumulation
- Accumulator Register
- Accuracy
- Ace
- Acellular
- Acentric Chromosome
- Acentric fragment
- Acephala
- Acetabulum
- Acetaldehyde
- Acetate
- Acetic acid
- Acetobacter
- Acetyl
- Acetyl Coenzyme A
- Acetyl-coa
- Acetylcholine
- Achenes
- Achilles reflex
- Achlorhydria
- Achromatic
- Achromia parasitica
- Achromotrichia
- Achylia pancreatica
- Acid
- Acid dye
- Acid indicator
- Acid Precipitation
- Acid Rain
- Acidic
- Acidity
- Acidophile
- Acidosis
- Acinar cells
- Acinetobacter guillouiae
- Acinetobacter junii
- Acinetobacter lwoffii
- Acme
- Acoelomate
- Acorn
- Acp
- Acquired
- Acquired sensitivity
- Acquired trait
- Acquisition
- Acrid
- Acroarthritis
- Acrobrachycephaly
- Acrocentric chromosome
- Acroesthesia
- Acromegaly
- Acromicria
- Acrosome
- Actin
- Actinopterygian
- Actinozoa
- Action
- Action potential
- Action Spectrum
- Activation
- Activation energy
- Activator
- Active
- Active Absorption
- Active acetate
- Active agglutination
- Active centre
- Active dry yeast
- Active immunity
- Active Ingredient
- Active methionine
- Active principle
- Active site
- Active transport
- Activity
- Acts
- Actual resource
- Acuity
- Acusection
- Acute
- Acute febrile illness
- Acyanogenic
- Ad
- Adair-koshland-nemethy-filmer model
- Adaptation
- Adaptations
- Adaptive
- Adaptive behaviour
- Adaptive evolution
- Adaptive radiation
- Adaptive trait
- Adaptive zone
- Adder
- Addiction
- Addisons clinical planes
- Addition
- Addition compound
- Additions
- Additive
- Additive effect
- Additive genes
- Address
- Adduction
- Adductor muscle
- Ade
- Adenine
- Adenine nucleotide
- Adenofibrosis
- Adenosine
- Adenosine diphosphate
- Adenosine monophosphate
- Adenosine triphosphate
- Adenylate
- Adequate
- Adequate stimulus
- Adfluvial
- Adherence
- Adherent
- Adhering junction
- Adhesion
- Adhesive
- Adient behaviour
- Adipectomy
- Adipocyte
- Adipose tissue
- Aditus laryngis
- Adjacent
- Adjunct
- Adjust
- Adjustment
- Adjutant
- Adjuvant
- Administer
- Administration
- Adnexa oculi
- Adnexum
- Adolescence
- Adoption
- Adrenaline
- Adsorption
- Adult
- Adultery
- Advance
- Advent
- Adventitious
- Adventitious bud
- Adventitious embryony
- Adventitious root
- Adverse effects
- Advocate
- Aerate
- Aeration
- Aerial
- Aerial mycelium
- Aerial Respiration
- Aerial root
- Aero-
- Aerobe
- Aerobic
- Aerobic bacteria
- Aerobic exercise
- Aerobic organism
- Aerobic process
- Aerobic respiration
- Aerosol
- Aerotolerant
- Aerotropism
- Aestivation
- Aetiolated
- Aetiological
- Aetiology
- Af
- Affect
- Affected
- Affection
- Afferent
- Afferent Nerve
- Afferent neuron
- Affinity
- Affinity chromatography
- Affirmation
- Affix
- Affluent
- Afrotropical realm
- Ag
- Agar
- Agar-agar
- Agarose
- Agave
- Age distribution
- Age groups
- Age-class
- Agent
- Agents
- Agglutination
- Agglutinin
- Agglutinogen
- Aggravation
- Aggregate fruit
- Aggregated lymphatic follicles
- Aggregated lymphatic nodules
- Aggregation
- Aggressin
- Aggression
- Agitation
- Agnathan
- Agonal rhythm
- Agonal thrombus
- Agonism
- Agonist
- Agonist muscle
- Agony
- Agranular endoplasmic reticulum
- Agranular leukocyte
- Agranulocyte
- Agretope
- Agriculture
- Ahaustral
- Ahf
- Aid
- Aids
- Ail
- Ailment
- Air
- Air bladder
- Air cell
- Air chamber
- Air conduction
- Air Pollution
- Air pressure
- Air sac
- Air Space
- Airway
- Airy disk
- Aitiology
- Akin
- Akinetes
- Al
- Ala
- Ala minor
- Ala orbitalis
- Ala ossis ilii
- Alanine
- Alar chest
- Alarmone
- Alb
- Alba
- Albers-Schonberg disease
- Albinism
- Albino
- Albumen
- Albumin
- Albuminoids
- Albuminous
- Albuminous cell
- Alcohol
- Alcoholic
- Alcoholic beverages
- Alcoholic Fermentation
- Aldehyde
- Aldohexoses
- Aldose
- Aldosterone
- Aldotriose
- Alethiology
- Aleurone Layer
- Alfilaria
- Algae
- Algal bloom
- Algology
- Algopsychalia
- Algorithm
- Alienation
- Aliment
- Alimentary canal
- Alimentary glycosuria
- Alimentary tract
- Aliphatic
- Aliphatic acids
- Aliphatic compound
- Aliquot
- Alive
- Alizarin
- Alkadienes
- Alkali
- Alkaline
- Alkaline reaction
- Alkalinity
- Alkaliphile
- Alkaloid
- Alkalosis
- All-Or-None-Law
- Allantois
- Allee effect
- Allele
- Allele frequency
- Allelic exclusion
- Allelism
- Allelopathy
- Allergen
- Allergy
- Allies
- Alligator
- Alliteration
- Allium
- Allogamy
- Allogeneic
- Alloimmunity
- Allometric Growth
- Allomone
- Allomorph
- Allopatric speciation
- Allopatry
- Allopolyploidy
- Allose
- Allosteric
- Allosteric Enzyme
- Allosteric Inhibitors
- Allotetraploid
- Allotropy
- Alloy
- Allozyme
- Alluvial Soil
- Alpaca
- Alpha hemolysis
- Alpha-amino acids
- Alpha-amylase
- Alpha-helix
- Alphaproteobacteria
- Alpine
- Alt
- Alteration
- Alternate
- Alternative
- Alternative hypothesis
- Altitude
- Alto
- Altrose
- Altruism
- Alum-haematoxylin
- Alveolalgia
- Alveolar air
- Alveolar cell
- Alveolar duct
- Alveolar gland
- Alveolar osteitis
- Alveolotomy
- Alveolus
- Amalgam
- Amalgamate
- Amalgamation
- Amaroidal
- Amastigote
- Amaurotic pupil
- Amber
- Ambient
- Ambiguity
- Ambiguous
- Ambiguous codon
- Ambulacral
- Amelanism
- Amenable
- Ametabolism
- Ametaboly
- Amharic
- Ami
- Amiable
- Amidase
- Amide
- Amide linkages
- Amination
- Amine
- Amino acid
- Amino acid sequence
- Amino group
- Amino sugar
- Amitosis
- Ammonia
- Ammonia assimilation
- Ammonification
- Ammonite
- Ammonium
- Ammonotelism
- Ammotherapy
- Amnion
- Amniote
- Amniotic Cavity
- Amniotic fluid
- Amniotic sac
- Amoeba
- Amoebic dysentery
- Amoebocyte
- Amoeboid
- Amoeboid movement
- Amorph
- Amorphia
- Amorphic mutation
- Amorphous
- Amount
- Amphiaster
- Amphibia
- Amphibian
- Amphibious
- Amphimixis
- Amphipathic
- Amphiphile
- Amphoteric
- Amphotonia
- Ampicillin resistance
- Ample
- Amplification
- Amplifier
- Amplifier host
- Amplify
- Amplitude
- Ampulla
- Amsterdam syndrome
- Amu
- Amyl
- Amyl valerate
- Amyloglucosidase
- Amyloplast
- Amylopsin
- Amylose
- Anabiosis
- Anabolic pathway
- Anabolic steroid
- Anabolism
- Anadromous
- Anadromous fish
- Anaemia
- Anaerobe
- Anaerobic
- Anaerobic bacteria
- Anaerobic exercise
- Anaerobic process
- Anaerobic respiration
- Anaesthesia
- Anaesthetic
- Anagenesis
- Anal
- Anal orifice
- Anal pit
- Anal pore
- Analgesic
- Analog
- Analogous
- Analogous structures
- Analogue
- Analogy
- Analysis
- Analyte
- Analytical
- Analyze
- Anamniote
- Anaphase I
- Anaphase II
- Anaphylactic shock
- Anaplasia
- Anarthropoda
- Anas
- Anastomoses
- Anastomosis
- Anathema
- Anatomical
- Anatomical plane
- Anatomy
- Ancestors
- Ancestral
- Ancestry
- Anchor
- Anchor splint
- Anchorage
- Anchorage independence
- Anchorage-independent cell
- Anchoring junction
- Anchors
- Ancillary
- Ancylostoma
- Ancylostoma duodenale
- Ancylostomiasis
- Andro-
- Androecium
- Androgen
- Androsterone
- Anemia
- Aneuploidy
- Anger
- Angiosperm
- Angiostenosis
- Angiotensinogen
- Angiotomy
- Angle
- Angle of mouth
- Angular
- Angular aperture
- Angulation
- Angulus sphenoidalis ossis parietalis
- Anhidrosis
- Animal
- Animal cell culture
- Animal Kingdom
- Animal pole
- Animal protein factor
- Animal testing
- Animalia
- Animals
- Animals suckling
- Animate
- Anion
- Anisogamy
- Anisotropic
- Anneal
- Annealing
- Annelida
- Annotated Diagram
- Annual
- Annual Ring
- Annular band
- Annular cartilage
- Annular lipid
- Annular Thickening
- Annulospiral ending
- Anodal opening contraction
- Anode rays
- Anoderm
- Anomalies
- Anomalous
- Anomalous trichromatism
- Anomaly
- Anomer
- Anomeric carbon
- Anoxia
- Anoxic
- Anoxygenic
- Answer
- Ant
- Ant thrushes
- Antagonism
- Antagonist
- Antagonistic effect
- Antagonistic Muscle
- Antarctic realm
- Ante cibum
- Antebrachium
- Antecardium
- Antecedent
- Antecubital fossa
- Antecubital space
- Antelope
- Antemortem thrombus
- Antenna
- Antennapedia
- Anterior
- Anterior crural nerve
- Anterior extremity
- Anterior funiculus
- Anterior nasal spine
- Anterior part
- Anterior pituitary
- Anterior primary division
- Anterior surface
- Anterolateral
- Anterolateral central arteries
- Anterolateral fontanel
- Anterolateral system
- Anthema
- Anther
- Anther cap
- Anther culture
- Antheridium
- Anthology
- Anthophore
- Anthozoan
- Anthracite
- Anthracosis
- Anthropogenic
- Anthropography
- Anthropoids
- Anthroponosis
- Anthropophilia
- Anthropophilic
- Antibacterial
- Antibiotic
- Antibody
- Antibody diversity
- Antibody-forming cell
- Anticoagulant
- Anticodon
- Antifungal
- Antifungicide
- Antigen
- Antigen-antibody complex
- Antigenic
- Antigenic variation
- Antigenicity
- Antihistamines
- Antimicrobial
- Antimorphic mutation
- Antioxidants
- Antiport
- Antisense strand
- Antisepalous
- Antiseptic
- Antiserum
- Antitoxin
- Antiviral
- Antivitamin
- Antrum
- Antrum of Highmore
- Anucleate
- Anus
- Anvil
- Aorta
- Apara
- Apathy
- Ape
- Apertura mediana ventriculi quarti
- Apertura pelvis superior
- Apertura thoracis superior
- Aperture
- Aperture function
- Apetalous
- Apex
- Apex of head of fibula
- Aphotic Zone
- Apical
- Apical bud
- Apical complex
- Apical Dominance
- Apical Growth
- Apical Meristem
- Apical meristem
- Apical plasma membrane
- Apicomplexa
- Apicomplexan
- Aplanospore
- Aplasia
- Apocarpous gynoecium
- Apocrine gland
- Apodous
- Apoenzyme
- Apolar
- Apomixis
- Apomorphy
- Aponeurorrhaphy
- Aponeurosis
- Apoplast
- Apoplectic cyst
- Apoptosis
- Aporepressor
- Apostate
- Apothegm
- Apparatus
- Apparent
- Apparent competition
- Apparent viscosity
- Apparition
- Appeal
- Appearance
- Appendage
- Appendages
- Appendages of eye
- Appendicular
- Appendix
- Appetitive behaviour
- Apple
- Apple jelly nodules
- Apple oil
- Application
- Applications
- Applied anatomy
- Applied science
- Apposition
- Appositional growth
- Approach-approach conflict
- Approach-avoidance conflict
- Approximation
- Apractagnosia
- Apragmatism
- Apron
- Aprophoria
- Aps
- Apt
- Apt test
- Apteria
- Aquaporin
- Aquarium
- Aquatic
- Aquatic locomotion
- Aquatic plant
- Aquatic plants
- Aquatic Respiration
- Aquatic root
- Aqueduct
- Aqueous
- Aqueous humor
- Aqueous solution
- Ara
- Arabinose
- Arable Farming
- Arachidonic acid
- Arachnida
- Arachnology
- Arbor
- Arboreal
- Arboreal locomotion
- Arch
- Archaea
- Archaean
- Archaebacteria
- Archaellum
- Archaeocyte
- Archaeopteryx
- Archaeplastida
- Archaic
- Archamoebae
- Archegonium
- Archenteron
- Archeocerebellum
- Arches
- Archetype
- Architecture
- Architeuthis
- Arctic
- Arcus venosus palmaris superficialis
- Arcus vertebrae
- Area
- Areal cover
- Arena
- Areola
- Areolar gland
- Areolar tissue
- Areole
- Arg
- Arginine
- Argipressin
- Argument
- Arguments
- Argyrophilic cell
- Ariel gazelle
- Aries
- Arise
- Aristotle
- Arm
- Armadillidiidae
- Armature
- Aroma
- Aromatase
- Aromatic compound
- Arousal
- Arrangement
- Arrangements
- Arrector pili muscles
- Arrectores pilorum
- Arrest
- Arrested tuberculosis
- Arrhenotoky
- Arrow poison
- Artefact
- Arterial embolism
- Arteriolar sclerosis
- Arteriole
- Arteriovenous shunt
- Artery
- Arthritis
- Arthrolithiasis
- Arthrology
- Arthropod
- Arthropodology
- Article
- Articular circumference of radius
- Articular facet
- Articular processes
- Articular surface
- Articulata
- Articulate
- Articulated skeleton
- Articulatio complexa
- Articulatio composita
- Articulatio radiocarpea
- Articulatio tarsi transversa
- Articulatio trochoidea
- Articulation
- Articulationes membri superioris liberi
- Artifact
- Artifactual
- Artificial
- Artificial active immunity
- Artificial passive immunity
- Artificial respiration
- Artificial Selection
- Artificially acquired active immunity
- Artificially acquired passive immunity
- Artiodactyla
- Asbestos
- Ascaricide
- Ascaris
- Ascaris lumbricoides
- Ascendant
- Ascending
- Ascending process
- Ascension
- Ascetic
- Ascidians
- Ascomycetes
- Ascospore
- Aseptic
- Asexual
- Ash
- Asialoglycoprotein
- Asian Glossy Starling
- Asn
- Asp
- Asparagine
- Asparagus
- Aspartame
- Aspartate
- Aspect
- Aspect ratio
- Aspergillus
- Aspermia
- Aspidium
- Aspirate
- Aspiration
- Aspire
- Ass
- Assam fever
- Assay
- Assert
- Assessment
- Assimilate
- Assimilation
- Assimilation pelvis
- Assist
- Associate
- Associates
- Association
- Association constant
- Association fibres
- Assortative mating
- Assortment
- Assumption
- Assumptions
- Ast
- Asteatosis
- Aster
- Asteraceae
- Asteroid
- Asteroids
- Asthenic personality
- Asthenic personality disorder
- Astomia
- Astragalus
- Astral microtubule
- Astrosphere
- Asymmetry
- Asymptomatic
- Atavism
- Athlete
- Atl
- Atmolysis
- Atmolyzation
- Atmos
- Atmosphere
- Atmospheric
- Atmospheric pressure
- Atmospherization
- Atom
- Atomic mass
- Atomic number
- Atomic theory
- Atomic weight
- Atomism
- Atomy
- Atopognosia
- ATP
- ATP synthase
- ATPase
- Atria
- Atrial natriuretic hormone
- Atrial syncytium
- Atrial systole
- Atriotomy
- Atrioventricular sulcus
- Atrioventricular valve
- Atrium
- Atrophy
- Att site
- Attachment
- Attachment sites
- Attenuated
- Attenuation factor
- Attract
- Attractant
- Attraction
- Attrition
- Atypical
- Au
- Audit
- Audition
- Auditory
- Auger
- Augmentation
- Aureole
- Auricle
- Auricula
- Auricular standstill
- Austin disease
- Australasia realm
- Autecology
- Authority figure
- Autism
- Auto-
- Autoactivation
- Autoantigen
- Autochthonous
- Autocrine
- Autogenous
- Autograph
- Autoimmune disease
- Autoimmunity
- Autolysis
- Automatic
- Automation
- Automixis
- Autonomic
- Autonomic nervous system
- Autonomous
- Autophagy
- Autophosphorylation
- Autophytic Plant
- Autopolyploidy
- Autopsy
- Autosomal
- Autosomal Inheritance
- Autosome
- Autospore
- Autotomy
- Autotroph
- Autotrophy
- Autotype
- Auxanographic method
- Auxanology
- Auxetic growth
- Auxiliary
- Auxin
- Auxochrome
- Auxotrophic mutant
- Auxotyping
- Avascular
- Avenue
- Average
- Aves
- Avian
- Avicennia germinans
- Avicula
- Avidity
- Avocation
- Avoidance Behaviour
- Avoidance conditioning
- Avoidance training
- Avoidance-avoidance conflict
- Ax
- Axenic culture
- Axes
- Axial
- Axial ametropia
- Axial angle
- Axial projection
- Axillary
- Axillary bud
- Axils
- Axis
- Axon
- Axon hillock
- Axon terminal
- Axoneme
- Axonogenesis
- Azoospermia