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n. Chiefly British A man's jersey undershirt.

n. Physics A multiplet with a single member.

n. A vest; a sleeveless garment with a low-cut neck, often worn underneath a shirt.

n. A multiplet having a single member, especially a single spectroscopic peak.

n. A quantum state having zero spin.

n. An unlined or undyed waistcoat; a single garment; -- opposed to doublet.

n. An unlined waistcoat: opposed to a doublet, which is lined.

n. An undershirt or undervest.

n. a collarless men's undergarment for the upper part of the body

"His chest muscles stood out through his thin singlet and his kilt was the size of a barrel."

doublet   

unmentionable    under-garment   

singlet oxygen   

Windbreaker    sweatshirt    undershirt    triplet    turtleneck    workshirt    sundress    sextet    camisole    talmit