Person, place, or thing (4)
I believe the answer is:
noun
'person place or thing' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for noun that I've seen before include "Part of speech identifying a person, place or thing" , "Substantive word" , "Naming word (grammar)" , "Word that refers to a person, place or thing" , "Type of word" .)