Was inquisitive about the numbers on keys (5)
I believe the answer is:
nosed
'was inquisitive' is the definition.
I can't tell whether this defines the answer.
'about the numbers on keys' is the wordplay.
'about' is a reversal indicator.
'the numbers' becomes 'son' (I am not sure about this - if you are sure you should believe this answer much more).
'on' means one lot of letters go next to another.
'keys' becomes 'de' (I've seen this in other clues).
'son' put after 'de' is 'deson'.
'deson' reversed gives 'NOSED'.
Can you help me to learn more?
(Other definitions for nosed that I've seen before include "Scented" , "Checked wine's aroma" , "edged out" , "Started judging wine, say" , "Eased" .)