Having a top that rolls away when not needed(adjective)
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Use "roll-top" in a sentence
"The big roll-top desk, the Dictaphone, and some of the other items on exhibit here appear in old photographs showing London at work."
"Nearby store owners spoke admiringly of the furniture they spotted Ms. Lee moving into her new headquarters, including a small roll-top desk she purchased for Mr. Cuomo's 14-year-old, Michaela, who occasionally stops by to do her homework."
"The case of the Apple II computer had originally included a Plexiglas cover, metal straps and a roll-top door."