Wave Muppet Republican inside (7)
I believe the answer is:
breaker
'wave' is the definition.
(breaker is a kind of wave)
'muppet republican inside' is the wordplay.
I cannot really understand how this works, but
'republican' could be 'r' (abbreviation) and 'r' is found within the answer.
The remaining letters 'beaker' is a valid word which might be clued in a way I don't see.
This may be the basis of clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for breaker that I've seen before include "from rider disciplining horse?" , "User of CB radio" , "Roller?" , "Large sea wave" , "A large wave, sounds destructive" .)