Channel close to Viking, say (6)
I believe the answer is:
gutter
'channel' is the definition.
(gutter is a kind of channel)
'close to viking say' is the wordplay.
'close to' says to take the final letters (the close/ending of).
'say' becomes 'utter' (I've seen this before**).
The final letter of 'viking' is 'g'.
'g'+'utter'='GUTTER'
(Other definitions for gutter that I've seen before include "Drainage channel" , "Where snipe can be found" , "piping?" , "Person who empties" , "Channel running along the eaves of a building" .)