anti

¹ American  

[an-tahy, an-tee] / ˈæn taɪ, ˈæn ti /

noun

plural

antis

1. a person who is opposed to a particular practice, party, policy, action, etc.

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anti- ² American  

1. a prefix meaning “against,” “opposite of,” “antiparticle of,” used in the formation of compound words (anticline ); used freely in combination with elements of any origin (antibody; antifreeze; antiknock; antilepton ).

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anti- ¹ British  

prefix

1. against; opposing

   anticlerical

   antisocial

2. opposite to

   anticlimax

   antimere

3. rival; false

   antipope

4. counteracting, inhibiting, or neutralizing

   antifreeze

   antihistamine

5. designating the antiparticle of the particle specified

   antineutron

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anti ² British  

/ ˈæntɪ /

adjective

1. opposed to a party, policy, attitude, etc

   he won't join because he is rather anti

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noun

1. an opponent of a party, policy, etc

anti– Scientific  

1. A prefix whose basic meaning is “against.” It is used to form adjectives that mean “counteracting” (such as antiseptic, preventing infection). It is also used to form nouns referring to substances that counteract other substances (such as antihistamine, a substance counteracting histamine), and nouns meaning “something that displays opposite, reverse, or inverse characteristics of something else” (such as anticyclone, a storm that circulates in the opposite direction from a cyclone). Before a vowel it becomes ant–, as in antacid.

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Sensitive Note

See homophobia.

Etymology

Origin of anti¹

First recorded in 1780–90; by shortening of words prefixed with anti-

Origin of anti-²

From Middle English, from Latin, from Greek, prefixal use of antí; akin to Sanskrit ánti “opposite,” Latin ante, Middle Dutch ende (giving rise to Dutch en “and”), English an- in answer. See ante-, and

Explanation

To be anti is to be opposed to or against something, like an action, political party, or government. If you are anti love scenes, you might prefer an action flick. The word anti comes from the prefix anti-, which means “against” or “opposite,” and is still used in English words, such as antibodies and anti-hero. As a word on its own anti is an adjective or preposition describing a person or thing that is against someone or something else. In a casual sense anti is sometimes used as a noun for a person who is against something — if you’re not on the pro side, you’re an anti.

Example Sentences

Over time, mapping where these enzymes are located and understanding their functions could help identify biomarkers for diagnosing cancer or reveal new weaknesses that anti cancer drugs could target.

From Science Daily • Mar. 9, 2026

Colombia's anti -narcotics strategy targets those at the top of the cocaine trade, not the dirt-poor farmers at the bottom.

From BBC • Feb. 3, 2026

Claire Bostrom-Smith, manager of King County’s health care-associated infections program, said in the blog post that C. auris is particularly concerning because it is resistant to common anti fungal medications.

From Seattle Times • Jan. 30, 2024

My parts in “Hazbin” are so crazy and anti who I am in real life.

From Los Angeles Times • Jan. 19, 2024

We did well to get enough for uniforms, bats, anti balls.

From "Life Is So Good" by George Dawson

Related Words

• adverse
• belligerent
• bitter
• contentious
• contrary
• hateful
• inhospitable
• inimical
• nasty
• opposed
• unfavorable
• unfriendly
• unsympathetic