the world > physical sensation > sleeping and waking > sleep > bed related to sleep or rest > [adverb] > in bed (4)
In bed. Now somewhat archaic.
Phrases and locutions belonging to preceding senses. Prepositional phrases: in, to, out of bed.
A large oblong piece of linen, cotton (or, formerly, hempen) cloth, used as an article of bedding, one being placed immediately above and one below…