The most common and most likely answer to this crossword clue is the 7 letter word GRUMBLE
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More clues leading to the result GRUMBLE
- Dog's last to find out about bitch
- Back from fishing, discover carp
- Protest ultimately ending with street fight
- Break down with new leader and complain
- Grouse making grand deep sound?
- Complain in centre of Vegas over gang fight there
- Good to discover the truth about beef
- Moan about investing money in food — the Parisian style
- Protest that’s good to latch on to
- Green and red tops with dirty blue get Monsieur to complain
Buddy explains!

The straight part
We know that "to complain" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case to complain = grumble.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does GRUMBLE mean?
GRUMBLE noun- A low thundering, rumbling or growling sound.
- The sound made by a hungry stomach.
- A surly complaint.
- To make a low, growling or rumbling noise, like a hungry stomach or certain animals.
- To complain; to murmur or mutter with discontent; to make ill-natured complaints in a low voice and a surly manner.
- To utter in a grumbling fashion.