Like two jacks in a deck of cards (3-4)
I believe the answer is:
one-eyed
'like two jacks in a deck of cards' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for one-eyed that I've seen before include "Monocular" , "Like the Jack of spades or hearts" , "''In the country of the blind, the . . .-. . . . man is King''" , "Like Cyclops" .)