The most common and most likely answer to this crossword clue is the 4 letter word ARID
I've seen this crossword clue in Independent
A
R
I
D
More clues leading to the result ARID
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The straight part
We know that "Dry" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case dry = arid.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 ARID mean?
ARID adjective- Very dry.
- Describing a very dry climate. Typically defined as less than 25 cm or 10 inches of rainfall annually.
- Devoid of value.