slang. Also 7 threpps, 8 threps. Short for THREEPENCE.

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a. 1700.  B. E., Dict. Cant. Crew, Threpps, Three-pence.

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1887.  J. C. Harris, Free Joe, etc. (1888), 60. A little boy who wanted to buy a thrip’s worth of candy went slowly out again after trying in vain to attract the attention of the hitherto prompt and friendly store-keeper.

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