During scare, lacking guts, not turning into this? (5)
I believe the answer is:
stone
'this?' is the definition.
The definition suggests a singular noun which matches the answer.
'during scare lacking guts not turning' is the wordplay.
'during' means one lot of letters goes inside another.
'lacking guts' means to remove the middle letters.
'turning' says the letters should be written backwards.
'scare' with its middle taken out is 'se'.
'not' back-to-front is 'ton'.
'se' enclosing 'ton' is 'STONE'.
'into' acts as a link.
(Other definitions for stone that I've seen before include "Hard lump of mineral matter" , "See 1" , "Seed of e.g. cherry" , "Gem; Staffs. town" , "Little rock" .)