The most common and most likely answer to this crossword clue is the 3 letter word DOR
D
O
R
More clues leading to the result DOR
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The straight part
We know that "Old rag" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case old rag = dor.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 DOR mean?
DOR noun- A large European dung beetle, Geotrupes stercorarius, that makes a droning noise while flying
- Any flying insect which makes a loud humming noise, such as the June bug or a bumblebee
- A trick, joke, or deception