Humble a bachelor on the quiet (5)
I believe the answer is:
abash
'humble' is the definition.
(I've seen this in another clue)
'a bachelor on the quiet' is the wordplay.
'bachelor' becomes 'BA' (the qualification: Bachelor of Arts).
'on' means one lot of letters go next to another.
'the quiet' becomes 'sh' (both can be said to tell someone to be quiet).
'a'+'ba'+'sh'='ABASH'
(Other definitions for abash that I've seen before include "Cause embarrassment" , "Rattle" , "Affront" , "Make embarrassed or ashamed" , "Cause to feel 4" .)