affinity

UK: /əˈfɪnɪti/ US: /əˈfɪnɪti/ ,(ə fin′i tē)

Inflections of 'affinity' (n): npl: affinities

WordReference Random House Learner's Dictionary of American English © 2026

af•fin•i•ty /əˈfɪnɪti/   n., pl. -ties. 

[~ + for/with/to/between]
1. a natural liking for or attraction to a person, thing, idea, etc:
   [uncountable] felt a sense of affinity with his new colleague.
   [countable] I felt a natural affinity for the group.
2. close resemblance, agreement, or connection due to a common ancestry:
   [countable] The Scandinavian languages have many affinities with German.
   [uncountable] Latin has affinity with Greek.

WordReference Random House Unabridged Dictionary of American English © 2026

af•fin•i•ty  (ə fin′i tē), n., pl. -ties., adj. 
n. 

1. a natural liking for or attraction to a person, thing, idea, etc.
2. a person, thing, idea, etc., for which such a natural liking or attraction is felt.
3. Sociology relationship by marriage or by ties other than those of blood (distinguished from consanguinity).
4. inherent likeness or agreement;
   close resemblance or connection.
5. Biology the phylogenetic relationship between two organisms or groups of organisms resulting in a resemblance in general plan or structure, or in the essential structural parts.
6. Chemistry the force by which atoms are held together in chemical compounds.

adj. 

7. of or pertaining to persons who share the same interests:
   to arrange charter flights for opera lovers and other affinity groups.

• Latin affīnitās connection by marriage. See affine, -ity
• Middle French
• Middle English affinite 1275–1325

Synonyms

• 1. partiality, fondness; sympathy, leaning, bent.
• 4. similarity, compatibility.

Antonyms

• 1. dislike, aversion.
• 4. dissimilarity, disparity.

Collins Concise English Dictionary © HarperCollins Publishers::

affinity / əˈfɪnɪtɪ/ noun ( -ties)

1. followed by with or for: a natural liking, taste, or inclination towards a person or thing
2. the person or thing so liked
3. a close similarity in appearance or quality; inherent likeness
4. relationship by marriage or by ties other than of blood, as by adoption
   Compare consanguinity
5. similarity in structure, form, etc, between different animals, plants, or languages
6. the tendency for two substances to combine; chemical attraction
7. a measure of the degree of interaction between two molecules, such as an antigen and antibody or a hormone and its receptor

Etymology: 14th Century: via Old French from Latin affīnitāt- connected by marriage, from affīnis bordering on, related

afˈfinitive adjective