Bob may be crusty about a point (7)
I believe the answer is:
curtsey
'bob' is the definition.
(I've seen this before)
'may be crusty about a point' is the wordplay.
'may be' is an anagram indicator.
'about' is an insertion indicator.
'a point' becomes 'e' (compass point).
'crusty' anagrammed gives 'curtsy'.
'curtsy' placed around 'e' is 'CURTSEY'.
(Other definitions for curtsey that I've seen before include "Gesture of respect" , "Formal greeting, bob" , "old form of obeisance" , "Girl's bob" , "Respectful greeting" .)