The most common and most likely answer to this crossword clue is the 4 letter word MOHO
M
O
H
O
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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 MOHO mean?
MOHO noun- The North Island takahē, an extinct rail of New Zealand.
- The Greek letter omega.
- Any of four Hawaiian birds of the genus Moho, formerly classed with the honeyeaters and now believed to be extinct.