The most common and most likely answer to this crossword clue is the 5 letter word DIGHT
D
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Buddy explains!
The straight part
We know that "Forgotten deck" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case forgotten deck = dight.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 DIGHT mean?
DIGHT verb- To deal with, handle.
- To have sexual intercourse with.
- To dispose, put (in a given state or condition).
- To compose, make.
- (of facial features) To be formed or composed (of).
- To furnish, equip.
- To dress, array; to adorn.
- To make ready, prepare.
- Disposed; adorned.
- Finely.