The most common and most likely answer to this crossword clue is the 6 letter word GROGGY
I've seen this crossword clue in Financial Times
G
R
O
G
G
Y
More clues leading to the result GROGGY
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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 GROGGY mean?
GROGGY adjective- Slowed or weakened, as by drink, sleepiness, etc.
- Of a horse: bearing wholly on its heels when trotting.