twin-size

or twin-sized

[ twin-sahyz ]
/ ˈtwɪnˌsaɪz /

adjective

(of a bed) approximately 39 inches (99 cm) wide and between 75 and 76 inches (191 and 193 cm) long; single.
pertaining to or made for a twin-size bed: twin-size sheets.

Origin of twin-size

First recorded in 1925–30
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

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