Sleep badly? (4)

I believe the answer is:

doss

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'sleep' is the definition.
(to doss is to sleep in an improvised bed)

I don't understand how the rest of the clue works.

Can you help me to learn more?

(Other definitions for doss that I've seen before include "Sleep like a tramp" , "Sleep - sleeping place" , "Sleep somewhere convenient" , "go to bed" , "In slang, sleep on sods" .)

I've seen this clue in the Evening Standard.

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