The most common and most likely answer to this crossword clue is the 5 letter word PLUMP
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The straight part
We know that "stout" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case stout = plump.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 PLUMP mean?
PLUMP verb- To grow plump; to swell out.
- To make plump; to fill (out) or support; often with up.
- To cast or let drop all at once, suddenly and heavily.
- To give a plumper (kind of vote).
- To give (a vote), as a plumper.
- To favor or decide in favor of something.
- Having a full and rounded shape; chubby, somewhat overweight.
- Fat.
- Sudden and without reservation; blunt; direct; downright.
- The sound of a sudden heavy fall.
- To drop or fall suddenly or heavily, all at once.
- Directly; suddenly; perpendicularly.
- A knot or cluster; a group; a crowd.