Vessel disturbing lagoon departs (7)
I believe the answer is:
gondola
'vessel' is the definition.
(gondola is a kind of vessel)
'disturbing lagoon departs' is the wordplay.
'disturbing' indicates an anagram (I've seen this in other clues).
'departs' becomes 'd' (common abbreviation e.g. train timetables).
'lagoon'+'d'='lagoond'
'lagoond' is an anagram of 'GONDOLA'.
(Other definitions for gondola that I've seen before include "Boats on the canals of Venice" , "Traditional boat of Venice" , "Palmieris' craft" , "Goon lad (anag.)" , "Venetian taxi" .)