Bet comedian is to meet queen (5)
I believe the answer is:
wager
'bet' is the definition.
('wager' can be a synonym of 'bet')
'comedian is to meet queen' is the wordplay.
'comedian' becomes 'wag' (I've seen this before).
'is to meet' says to put letters next to each other.
'queen' becomes 'er' (abbreviation for Elizabeth Regina).
'wag'+'er'='WAGER'
(Other definitions for wager that I've seen before include "Put on a bit" , "Risk; stake" , "Punt" , "Bet, gamble" , "One making pledge" .)