Look up and down (4)

I believe the answer is:

peep

I believe this clue is a double definition.

'look' is the first definition.
(peep can mean to look at something)

'up and down' is the second definition.

(Other definitions for peep that I've seen before include "Look quickly" , "Look furtively or voyeuristically" , "Large underground chamber" , "Look secretly" , "Palindromic glimpse" .)

I've seen this clue in the Universal and The Sun.

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