Come about old dog biting Charlie (5)
I believe the answer is:
occur
'come about' is the definition.
(synonyms)
'old dog biting charlie' is the wordplay.
'old' becomes 'o' (common abbreviation eg in OE for Old English).
'dog' becomes 'cur' (both can mean a despicable person).
'biting' means one lot of letters goes inside another (some letters bite or swallow others).
'charlie' becomes 'C' (phonetic alphabet: alpha, bravo, charlie etc.).
'cur' placed around 'c' is 'ccur'.
'o'+'ccur'='OCCUR'
(Other definitions for occur that I've seen before include "Spring to mind" , "appear" , "Come to pass" , "Turn up" , "crop up" .)