Strong drink some fear a killer (4)
I believe the answer is:
arak
'strong drink' is the definition.
(arak is a kind of strong drink)
'some fear a killer' is the wordplay.
'some' indicates a hidden word (some of the parts of the word are used).
'ARAK' is hidden within 'fear a killer'.
(Other definitions for arak that I've seen before include "Strong drink distilled from fermented molasses" , "spirit from the East" , "An alcoholic drink" .)