affinity

American  

[uh-fin-i-tee] / əˈfɪn ɪ ti /

noun

plural

affinities

1. a natural liking for or attraction to a person, thing, idea, etc.

   Synonyms:

   bent, leaning, sympathy, fondness, partiality

   Antonyms:

   aversion, dislike

2. a person, thing, idea, etc., for which such a natural liking or attraction is felt.

3. relationship by marriage or by ties other than those of blood (distinguished from consanguinity).

4. inherent likeness or agreement; close resemblance or connection.

   Synonyms:

   compatible, similarity

   Antonyms:

   disparity, dissimilarity

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.

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adjective

1. of or relating to persons who share the same interests.

   to arrange charter flights for opera lovers and other affinity groups.

affinity British  

/ əˈfɪnɪtɪ /

noun

1. 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. chem

   1. the tendency for two substances to combine; chemical attraction

   2.  A.  a measure of the tendency of a chemical reaction to take place expressed in terms of the free energy change

7. biology a measure of the degree of interaction between two molecules, such as an antigen and antibody or a hormone and its receptor

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affinity Scientific  

/ ə-fĭn′ĭ-tē /

1. A relationship or resemblance in structure between species that suggests a common origin.

2. An attraction or force between particles that causes them to combine, as the attraction between an antigen and an antibody.

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Other Word Forms

• affinitive
  adjective
• nonaffinity
  noun

Etymology

Origin of affinity

First recorded in 1275–1325; Middle English affinite, from Middle French, from Latin affīnitās “connection by marriage”; equivalent to affine + -ity

Explanation

If you get along with someone very well, you have an affinity with them. Sometimes opposites attract, so you might feel a strange affinity to someone who is seemingly very different from you. When you are attracted to someone or something a great deal, we say that you have an affinity, a natural connection. Likewise, scientists use affinity to describe organisms that are alike or resemble each other. Interestingly, the Middle English word, affinite, originally applied to people who were connected or related by marriage, rather than by biology.

Example Sentences

The termination notice comes nearly a year after Affinity Gaming ended 24/7 operations at Buffalo Bill’s Resort on July 6.

From Los Angeles Times • May 6, 2026

An early version of Paramount’s bid also initially included backing from Chinese company Tencent and Affinity Partners, the private-equity firm founded by President Trump’s son-in-law Jared Kushner.

From The Wall Street Journal • Apr. 5, 2026

People can also add in a “variability cost” budget line, said Grant Gallagher, director of financial well-being at Affinity Federal Credit Union.

From MarketWatch • Feb. 19, 2026

This year’s Horse friends, who make up a Triangle of Affinity on the Zodiac circle, are the Tiger and Dog.

From Los Angeles Times • Feb. 10, 2026

The Inanition or Emptiness, though accompanied with Symptoms different from the former, have yet some Affinity to them with Respect to their Cause, which is a kind of general Exsiccation or Dryness.

From Advice to the people in general, with regard to their health by Tissot, S. A. D. (Samuel Auguste David)

Related Words

• affection
• closeness
• fondness
• leaning
• rapport
• sympathy
• weakness