suffix

In linguistics, the suffix is part of the word that's added onto the end, like the -ish in foolish.

When a suffix is added to a word, it changes the form, like when adding the suffix -y turns the noun soap into the adjective soapy. You can also use suffix as a verb. If you suffix the word cake with -less, you end up cakeless, which is pretty sad, especially if it's your birthday.

Definitions of suffix
1

n an affix that is added at the end of the word

Synonyms:
postfix
Type of:
affix
a linguistic element added to a word to produce an inflected or derived form
ending, termination
the end of a word (a suffix or inflectional ending or final morpheme)

v attach a suffix to

suffix words”
Antonyms:
prefix
attach a prefix to
Type of:
affix
attach or become attached to a stem word