Radiate, give off (4)
I believe the answer is:
emit
This clue is a double definition.
'radiate' is the first definition.
(I've seen this in another clue)
'give off' is the second definition.
(synonyms)
(Other definitions for emit that I've seen before include "'Give out, light say (4)'" , "Release" , "Issue" , "Give out or pour forth" , "Give out or put forth" .)