Gad about, like pirates at sea? (7)
I believe the answer is:
traipse
'gad about' is the definition.
(thesaurus)
'pirates at sea?' is the wordplay.
'at sea?' is an anagram indicator (I've seen 'at sea' mean this).
'pirates' anagrammed gives 'TRAIPSE'.
'like' is the link.
(Other definitions for traipse that I've seen before include "Pirates (anag) -- walk without 9" , "laborious walk" , "long tiring walk" , "Walk heavily" , "Trudge around" .)