Alertness of girl soldier caught in narrow passage (9)
I believe the answer is:
vigilance
'alertness' is the definition.
(I know that alertness can be written as vigilance)
'girl soldier caught in narrow passage' is the wordplay.
I cannot quite see how this works, but
'girl' could be 'vi' (short for Violet) and 'vi' is located in the answer.
'soldier' could be 'gi' (term for US soldier) and 'gi' is found within the answer.
'caught' could be 'c' (cricket abbreviation) and 'c' is found in the answer.
'passage' could be 'lane' (I've seen this before) and 'lane' is found within the leftover letters.
No letters remain.
This may be the basis of the clue (or it may be nonsense).
'of' acts as a link.
Can you help me to learn more?
(Other definitions for vigilance that I've seen before include "Alertness, watchfulness" , "Keeping careful watch on" .)