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sport shirt vs. dress shirt

sport shirt

Or sports shirt

noun

a long- or short-sleeved soft shirt for informal wear by men, having a squared-off shirttail that may be left outside the trousers, usually worn without a tie.

dress shirt

noun

a man's shirt worn for formal or semiformal evening dress, usually having French cuffs and a stiff or pleated front to be fastened with studs.
a man's shirt, buttoning down the front and typically having long sleeves with barrel or French cuffs, and a soft or starched collar, worn with a necktie.