Conveyance gets round in racket (4)
I believe the answer is:
boat
'conveyance' is the definition.
(boat is a kind of conveyance)
'round in racket' is the wordplay.
'round' becomes 'o' (round can mean a round object).
'in' means one lot of letters goes inside another.
'racket' becomes 'bat' (bat is a kind of racket).
'o' put inside 'bat' is 'BOAT'.
'gets' acts as a link.
(Other definitions for boat that I've seen before include "See 1" , "Water craft" , "Small ship" , "See 18" , "See 12 Down" .)