Very keen to conceal hole for escape (5)
I believe the answer is:
avoid
'for escape' is the definition.
(I've seen this before)
'very keen to conceal hole' is the wordplay.
'very keen' becomes 'avid' (I've seen this before).
'to conceal' indicates putting letters inside.
'hole' becomes 'O' (O looks like a hole).
'avid' going around 'o' is 'AVOID'.
(Other definitions for avoid that I've seen before include "Shy away from" , "(If you can't 10), keep away from" , "Stay away from or circumvent" , "Run away from" , "Get out of" .)