The predicate of a sentence (4)
I believe the answer is:
verb
'the predicate of a sentence' is the definition.
(I've seen this before)
This is all the clue.
(Other definitions for verb that I've seen before include "A word that conveys action" , "Maybe protest" , "Part of speech" , "love, for example" , "Word such as run, make, or do" .)