The most common and most likely answer to this crossword clue is the 10 letter word MATTRESSES
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More clues leading to the result MATTRESSES
Buddy explains!

The straight part
We know that "Parts of beds" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case parts of beds = mattresses.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 MATTRESSES mean?
MATTRESSES noun- A pad on which a person can recline and sleep, usually having an inner section of coiled springs covered with foam or other cushioning material then enclosed with cloth fabric.
- A form of retaining wall used to support foundations or an embankment