A task given as a punishment. Of course the word is taken from the verb impose, as the task is imposed. The term is common in schools, colleges, and universities. In the sense of a deception it means to “put a trick on a person,” hence, the expressions “to put on one.” “to lay it on thick,” etc.
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894
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