What does "nightshirt" mean?

A shirt-like garment (often oversized) that is worn to bed.

What is a synonym for "nightshirt"?

Common synonyms include: bed shirt, sleep shirt, sleepwear top.

noun

noun ·2 syllables ·Rare ·Advanced level

Noun

1
A shirt-like garment (often oversized) that is worn to bed.
"He wore a blue striped nightshirt and bedroom slippers."
2
nightclothes worn by men wordnet

""Give Tom a decent nightshirt," ordered Nan. "I don't rate those pyjamas.""

From night + shirt.