Smart aleck (4-3)
'smart aleck' is the definition.
(I've seen this before)
This is all the clue.
(Other definitions for know-all that I've seen before include "One who thinks they have all the answers" , "Clever clogs!" , "One supposedly omniscient" , "Boastful person who behaves like repository of information" , "Self-styled polymath" .)
'smart aleck' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for know-it-all that I've seen before include "Smart alec" , "Unteachable bigot" .)