A prefix is a letter or group of letters added to the beginning of a word to make a new word.

Here we look at five common prefixes.

anti-
opposed to or against; opposite of or preventing
The noise of anti-aircraft fire could be heard.
Her anti-violence views are well known.
An anti-corruption investigation is taking place.

co-
together; with:
co-ownership
a co-writer/co-author
Appalling poverty and great wealth coexist in the city.

com-
together; with:
combination
community
companions

de-
used to add the meaning ‘opposite’, ‘remove’ or ‘reduce’ to a noun or verb:
the deforestation of the rainforests
the denationalization of the coal industry
Once you’ve written a computer program, you have to debug (= remove the errors from) it.

dis-
added to the front of some words to form their opposites: ^
to disagree
a dishonest person