1. a loose garment worn for sleeping, typically by women and girls
Usage: chiefly British English; American English more commonly uses 'nightgown' or 'nightshirt'

Examples

• She put on her cotton nightdress before bed.
• The store sells a variety of nightdresses in different colors and sizes.
• My grandmother always wore a long nightdress to sleep.
• The nightdress was soft and comfortable for sleeping.
• She packed several nightdresses for her trip to the hospital.