A seaman stationed in the waist of a warship.(noun)
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Use "waister" in a sentence
"They could not be got upon deck in the night, or if by dint of the rope's-end they were at length routed out of their hammocks, they immediately developed the worst symptoms of the "waister" -- seasickness and fear of that which is high."
"What I like most about it is that it's not a shirt waister."
"Sally had grimaced with distaste when she had met her from the train, immediately condemning the beige shirt waister dress she was wearing as unbelievably frumpy and sexless."