See western monarch more humble? (5)
I believe the answer is:
lower
'more humble?' is the definition.
('low' can be a synonym of 'humble')
'see western monarch' is the wordplay.
'see' becomes 'lo' ('lo' is an archaic exclamation meaning 'look!').
'western' becomes 'w'.
'monarch' becomes 'ER' (abbreviation for Elizabeth Regina, British Queen).
'lo'+'w'+'er'='LOWER'
(Other definitions for lower that I've seen before include "Lessen" , "Move something down" , "put down" , "Reduce" , "Hereford, say" .)