Rower from Oslo arrives (3)
I believe the answer is:
oar
'rower' is the definition.
(I've seen this in another clue)
'from oslo arrives' is the wordplay.
'from' says the answer is hidden in the clue.
'OAR' is hidden within 'oslo arrives'.
(Other definitions for oar that I've seen before include "Sportsman" , "Rower's flat blade" , "spoon?" , "Rower's implement" , "Scull" .)