The definition of ative is relating to or serving to.
An example of ative used as a suffix is in the word informative, which means relating to give information.
of or relating to, serving to, tending to: demonstrative, informative, talkative
Origin of -ative; from French or L; French -atif, feminine -ative ; from Classical Latin -ativus
Of, relating to, or associated with: talkative.
Origin of -ativeMiddle English, from Old French -atif, -ative, from Latin -at&imacron;vus, from -atus, past participle suff.; see –ate1.