Escort vessel taking line through ducks (6)
I believe the answer is:
gigolo
'escort' is the definition.
(I've seen this before)
'vessel taking line through ducks' is the wordplay.
'vessel' becomes 'gig' (gig is a kind of vessel).
'taking' means one lot of letters go next to another.
'line' becomes 'l'.
'through' indicates putting letters inside (I've seen this in other clues).
'ducks' becomes 'oo' (I've seen this in other clues).
'l' inserted inside 'oo' is 'olo'.
'gig'+'olo'='GIGOLO'
(Other definitions for gigolo that I've seen before include "Old word for man maintained by rich woman" , "Man paid by older woman to be her lover" , "Man supported by an older woman to be her lover" , "Lounge lizard" , "Hired male escort" .)