Rower in Tromso arriving (3)
I believe the answer is:
oar
'rower' is the definition.
(I've seen this before)
'in tromso arriving' is the wordplay.
'in' indicates the answer is hidden within the clue.
'OAR' is hidden in the letters of 'tromso arriving'.
(Other definitions for oar that I've seen before include "propellor" , "Propelling blade" , "One of an eight" , "Bladed pole" , "Pusher" .)