Affected courage can keep you alive - for a while (10,5)

'a while' is the definition.
Although both the answer and definition are singular nouns, I cannot see how one could define the other.

'affected courage can keep you alive' is the wordplay.
I cannot quite understand how this works, but
'affected' could be 'artificial' (similar in meaning) and 'artificial' is found within the answer.
'courage' could be 'heart' (heart is a kind of courage) and 'heart' is found in the answer.
This accounts for all the letters.
This explanation may well be incorrect...

'for' is the link.

Can you help me to learn more?