Dictionary > Affinity


noun, plural: affinities
(1) (taxonomy) The resemblances in structure between two organisms or between biological populations implicating that they are of a common origin, type or stock
(2) (chemistry) The attractive force binding atoms in molecules; the tendency to combine and form bonds in a chemical reaction
(3) (immunology) The attraction or the stereochemical compatibility between an antibody and an antigen
(4) An inherent likeness or relationship; an attraction for a particular element, organ, or structure
In general, affinity pertains to the attraction or compatibility between particles, elements, structures, or things. It may be used to refer to the attractive force causing the particles or chemicals to combine. It may also be used to describe the degree at which molecules are likely to combine, such as the affinity of hemoglobin for oxygen, or that between an antibody and an antigen, or of a protein-ligand binding strength.
In taxonomy, affinity pertains to (a measure of) the resemblance of one organism (or one population) to another. Their similarities may suggest a common origin. It may also be relevant in the classification as well as the relationship of the specimen to other taxonomic groups.
Related term(s):

  • Low affinity platelet factor iv
  • Affinity column
  • Affinity labeling
  • Affinity labels
  • Affinity tag
  • Affinity constant
  • Oxygen affinity anoxia
  • Affinity chromatography
  • Affinity adsorbent
  • Antibody affinity

Mentioned in:

  • Chromaffin cell
  • Biotin
  • Bacteriophage
  • Avidity

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