On one's heels, apt to burn? (3)
I believe the answer is:
hot
'apt to burn?' is the definition.
I can't tell whether this defines the answer.
'on one's heels' is the wordplay.
'on' indicates putting letters inside (as in clothing 'on' a person).
'one' becomes 'o' (I've seen this in other clues).
'heels' becomes 'ht' (I can't explain this - if you can you should believe this answer much more).
'o' put inside 'ht' is 'HOT'.
Can you help me to learn more?
(Other definitions for hot that I've seen before include "Flaming - stolen" , "Torrid" , "(Of goods) stolen (colloq.)" , "Stolen - sought after" , "(Of food) spicy" .)