Suffix
noun
(grammar) A morpheme added at the end of a word to modify the word's meaning.
“The suffix "-able" changes "sing" into "singable".”
A subscript.
A final segment of a string of characters.
“The string "abra" is both a prefix and a suffix of the string "abracadabra".”
Synonyms: affix
verb
To append (something) to the end of something else.