Prefix · against / opposition
Signals active opposition or protection: antibiotic, antivirus, antisocial, antidote.
Written by Bryan López, English teacher · Updated
Anti- comes from Greek and means "against". It is used for something that actively opposes another thing or protects you from it. If a word starts with anti-, there is an "against" or a "protects from" in its meaning.
Anti- is a stance: someone or something that opposes and fights against something. Non- only says that something is not a certain way, without taking sides. It is the difference between being against something and simply not being part of it. If you want to express opposition, anti- is your prefix.
Attaches to nouns and adjectives. Modern English usually writes it without a hyphen:
Pronunciation: /ˈænti/ in British and formal American English; /ˈæntaɪ/ in casual American English. Both are widely accepted.
anti-/ˈænti/ or /ˈæntaɪ/
Tap the button to hear how the prefix sounds. Each word in the table has its own audio.
In formal English, "antisocial behaviour" describes conduct harmful to society. In casual American use it may mean someone who prefers not to socialise, but the formal sense is stronger and used in legal contexts.
A trick to remember it
Think of antibiotics fighting bacteria: anti- = against, or protection against something. antibiotic, antivirus.
Exercise 1 · Form the word
Exercise 2 · Pick the right one
"An ___ is a substance that neutralises a poison or harmful effect in the body."
Exercise 3 · Pick the right one
What is the difference between "antisocial" and "unsociable"?
The prefix anti- signals active opposition or protection: antibiotic, antivirus, antisocial, antidote.
The prefix anti- is pronounced /ˈænti/ or /ˈæntaɪ/. For example, "antibiotic".
"biotic" becomes "antibiotic". It is a typical example of the anti- prefix.
un-, re-, pre-, dis-, over-, in-... every beginning you need to unlock thousands of English words at once.