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 (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.

---

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

---

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.

---

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

That increased affinity suggests that Spanish isn’t going away anytime soon.

From Los Angeles Times • Apr. 11, 2026

The narrator’s mishandling of his cellphone reprises the author’s delightful affinity for physical slapstick.

From The Wall Street Journal • Mar. 31, 2026

The Canadian star has long had an affinity for the city.

From BBC • Mar. 30, 2026

One of the the biggest stock-market stories of 2026 so far has been investors’ growing affinity for value stocks.

From MarketWatch • Mar. 18, 2026

They engaged a powerful affinity with their habitat and their food chain.

From "The Poisonwood Bible" by Barbara Kingsolver

Related Words

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