Odd crew at sea, cramped (7)
I believe the answer is:
crowded
'cramped' is the definition.
(thesaurus)
'odd crew at sea' is the wordplay.
'at sea' indicates anagramming the letters.
'odd'+'crew'='oddcrew'
'oddcrew' anagrammed gives 'CROWDED'.
(Other definitions for crowded that I've seen before include "Squeezed full of people" , "cramped" , "With too many people" , "Thronged, overfilled" , "Jam-packed" .)