Punctuation (5)
I believe the answer is:
colon
'punctuation' is the definition.
(I know that colon is a type of punctuation)
This is all the clue.
(Other definitions for colon that I've seen before include "Panama port; part of intestine" , "Part of the intestine - punctuation mark" , "Part of body; some punctuation" , "Punctuation mark; gut" , "cash" .)