Lose nerve? Not on your life! (5)
I believe the answer is:
never
'not on your life' is the definition.
I can't tell whether this defines the answer.
'lose nerve?' is the wordplay.
'lose' indicates an anagram (I've seen 'lost' mean this).
'nerve' anagrammed gives 'NEVER'.
Can you help me to learn more?
(Other definitions for never that I've seen before include "Not in a month of Sundays" , "Not in a million years!" , "Strong negative" , "'It's now or - - ' (14 song)" , "At no time whatever" .)