Blackstone says hotch-pot is a pudding made of several things mixed together. Lands given in frank-marriage or descending in fee-simple are to be mixed, like the ingredients of a pudding, and then cut up in equal slices among all the daughters. (Book ii. 12.)
As to personality: Hotch-pot may be explained thus: Suppose a father has advanced money to one child, at the decease of the father this child receives a sum in addition enough to make his share equal to the rest of the family. If not content, he must bring into hotch-pot the money that was advanced, and the whole is then divided amongst all the children according to the terms of the will.
French, hochepot, from hocher, to shake or jumble together; or from the German hoch-pot, the huge pot or family caldron. Wharton says it is haché en poche.
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894
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