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Biology Dictionary: O

Search or browse the dictionary for the definition of biology terms starting with the letter “O”.

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Dictionary > O
AllC

O

  • O antigen
  • Oar
  • Oasthouse urine disease
  • Ob
  • Obdiplostemonous
  • Obelisk
  • Obermayers test
  • Obesity
  • Object
  • Objective
  • Objectives
  • Objects
  • Oblate
  • Obligate
  • Obligate aerobe
  • Obligate anaerobe
  • Obligate mutualism
  • Obligate parasite
  • Oblique
  • Oblique muscle
  • Obliterate
  • Obscure
  • Observation
  • Observer
  • Obsolete
  • Obstinate
  • Obstruction
  • Occiput
  • Occlusion
  • Occult
  • Occultation
  • Occupations
  • Ocean
  • Oceanian realm
  • Octapeptide
  • Octology
  • Octoploid
  • Ocular
  • Ocular micrometer
  • Oculocutaneous albinism
  • Ocyte
  • Odd-pinnate
  • Odds
  • Odontophore
  • Odontoprisis
  • Oedema
  • Oesophagus
  • Oestrous Cycle
  • Oestrus
  • Offensive
  • Offset
  • Offsets
  • Offshoot
  • Offspring
  • Ohngrens line
  • Oil
  • Oil retention enema
  • Oils
  • Ointment bases
  • Okazaki fragment
  • Old World monkey
  • Olecranon
  • Oleoresin
  • Olfactory
  • Olfactory nerve
  • Olfactory receptor cells
  • Oligohydramnios
  • Oligonucleotide
  • Oligopeptide
  • Oligosaccharide
  • Oligospermia
  • Ology
  • Olympian forehead
  • Omega
  • Omega-6 fatty acid
  • Ominous
  • Omission
  • Omit
  • Omniscient
  • Omnivore
  • Omnivorous diet
  • Oncogene
  • Onion
  • Online systems
  • Ontogenesis
  • Ontogeny
  • Onych-
  • Onychatrophia
  • Oocyst
  • Oocyte
  • Oogenesis
  • Oogonium
  • Ookinete
  • Oospore
  • Ootid
  • Ooze
  • Opacity
  • Opaque
  • Opaque microscope
  • Open circulatory system
  • Open Population
  • Open system
  • Open tuberculosis
  • Opera
  • Operant conditioning
  • Operation
  • Operator
  • Operator gene
  • Operator region
  • Operculum
  • Operon
  • Operon Model
  • Ophiuroidea
  • Ophthalmomalacia
  • Opine
  • Opisthaptor
  • Opisthomastigote
  • Opportunistic
  • Opportunistic pathogen
  • Oppose
  • Opposite
  • Opposition
  • Opsonin
  • Opsonization
  • Optical
  • Optical density
  • Optically active
  • Optimal
  • Optimum
  • Opuntia
  • Ora
  • Oral
  • Oral cavity
  • Oral vestibule
  • Orange
  • Orbicularis oris
  • Orbiculated
  • Orbit
  • Orbital
  • Orbits
  • Orchestra
  • Orchids
  • Orcinol
  • Orcinol test
  • Ord
  • Order
  • Ordinal
  • Ordinate
  • Ordination
  • Ore
  • Orexia
  • Organ
  • Organ culture
  • Organ specificity
  • Organ-specific antigen
  • Organa oculi accessoria
  • Organa sensuum
  • Organic
  • Organic acid
  • Organic catalyst
  • Organic chemistry
  • Organic compound
  • Organic matter
  • Organic molecule
  • Organic synthesis
  • Organism
  • Organization
  • Organizational affiliation
  • Oriental
  • Orientation
  • Orienting reflex
  • Orifice
  • Origin
  • Origin of replication
  • Originals
  • Ornithine
  • Ornithology
  • Oro
  • Oropharynx
  • Orotic acid
  • Orthodox
  • Orthogonal
  • Orthologous Gene
  • Orthology
  • Os
  • Os multangulum minus
  • Os uteri internum
  • Oscillation
  • Oscilloscope
  • Osculum
  • Osmoreceptor
  • Osmoregulation
  • Osmotic lysis
  • Osmotic Potential
  • Osmotic pressure
  • Osmotolerance
  • Osmotrophy
  • Ossa digitorum
  • Ossa membri superioris
  • Osseous tissue
  • Ossicles
  • Ossicular chain
  • Ossification
  • Ostempyesis
  • Ostentatious
  • Osteoblast
  • Osteoclast
  • Osteocyte
  • Osteomalacia
  • Osteon
  • Osteopetrosis
  • Osteoporosis
  • Ostia venarum pulmonalium
  • Ostium
  • Ostrich
  • Otary
  • Otic
  • Otodynia
  • Otolith
  • Out of Africa model
  • Outbreak
  • Outbreeding
  • Outer membrane
  • Outgroup
  • Outlet
  • Output
  • Outwelling
  • Ova
  • Ovalbumin
  • Ovarian cycle
  • Ovarian fossa
  • Ovary
  • Ovate
  • Oven dry ton
  • Overbank flooding
  • Overdominance
  • Overgrowth
  • Overhang
  • Overlap
  • Overlapping
  • Overlapping genes
  • Overlay
  • Overshoots
  • Overstory
  • Overventilation
  • Oviduct
  • Oviparous
  • Ovocyte
  • Ovoid
  • Ovoviviparous
  • Ovulation
  • Ovule
  • Ovum
  • Owe
  • Owl
  • Ox
  • Oxaloacetate
  • Oxic
  • Oxidant
  • Oxidase
  • Oxidation-fermentation test
  • Oxidation-reduction
  • Oxidative metabolism
  • Oxidative phosphorylation
  • Oxidise
  • Oxidize
  • Oxidizer
  • Oxidizing agent
  • Oxidoreductase
  • Oxy-
  • Oxygen
  • Oxygen capacity
  • Oxygen consumption
  • Oxygen Debt
  • Oxygen deficit
  • Oxygen dependent killing
  • Oxygenase
  • Oxygenic
  • Oxyhemoglobin
  • Oxytocin
  • Oyster
  • Ozochrotia
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