The most common and most likely answer to this crossword clue is the 7 letter word ZITHERS
I've seen this crossword clue in The Daily Telegraph
Z
I
T
H
E
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S
More clues leading to the result ZITHERS
Buddy explains!
The straight part
We know that "instruments" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case instruments = zithers.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 ZITHERS mean?
ZITHERS noun- A musical instrument consisting of a flat sounding box with numerous strings placed on a horizontal surface, played with a plectrum or fingertips.
- (translations) Related or similar instruments in other cultures, such as the Chinese guqin or Norwegian harpeleik; especially any chordophone without a neck, and with strings that pass over the body.