Originally, in India, loose drawers or trousers, such as those worn, tied about the waist, by Mohammedan men and women; by extension, a similar garment adopted among Europeans, Americans, etc., for wear in the dressing room and during sleep; also, a suit consisting of drawers and a loose upper garment for such wear.
A garment, similar to the Oriental pyjama (which see), adopted among Europeans, Americans, and other Occidentals, for wear in the dressing room and during sleep; also, a suit of drawers and blouse for such wear.
Sometimes I'm so tired, I look down at what I'm wearing, and if it's comfortable enough to sleep in, I don't even make it into my pajamas. I'm looking down, and I'm like, 'T-shirt and stretchy pants? Yup, that's fine. It's pajama-y, good night.' Rebecca Romijn
I remember seeing a movie with Jose Ferrer and Rosemary Clooney where they were husband and wife, and they got in bed, and he had on polka-dot pajamas and she had on striped pajamas, and when they got up the next morning he had on the striped pajamas and she had the polka dot pajamas, and that was considered racy at that time! Bob Newhart