Vessel bachelors get in? (5)
I believe the answer is:
basin
'vessel' is the definition.
(basin is a kind of vessel)
'bachelors get in?' is the wordplay.
'bachelors' becomes 'bas' (people with Bachelor of Arts degrees).
'get' is a charade indicator (letters next to each other).
'bas'+'in'='BASIN'
(Other definitions for basin that I've seen before include "Region drained by a river" , "Sink for washing" , "River-drained area" , "Round open dish for washing" , "requirement for cleansing" .)