• Webster's Revised Unabridged Dictionary
    • n Assumpsit (Law) A promise or undertaking, founded on a consideration. This promise may be oral or in writing not under seal. It may be express or implied.
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Century Dictionary and Cyclopedia
    • n assumpsit In law: An action lying for the recovery of damages sustained through the breach of a simple contract (that is, a promise not under seal), in which the plaintiff alleges that the defendant assumpsit, that is, promised or undertook, to perform the act specified. Hence— An actionable promise, express or implied by law. In England and in most of the United States this, like the other common-law forms of action, has been superseded by statute.
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Chambers's Twentieth Century Dictionary
    • n Assumpsit a-sump′sit an action at law, wherein the plaintiff asserts that the defendant undertook (L. assumpsit) to do a certain act and failed to fulfil his promise: in the United States, the most common form of action.
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Webster's Revised Unabridged Dictionary
L., he undertook, pret. of L. assumere,. See Assume


In literature:

If you choose to make an assumpsit, I'm sure I shall not object to the security.
"The Absentee" by Maria Edgeworth
The distinctions between debt, covenant, and assumpsit are merely historical.
"The Path of the Law" by Oliver Wendell Holmes, Jr.
Lord Holt was well aware that the use of an assumpsit was not confined to contract.
"The Common Law" by Oliver Wendell Holmes, Jr.
Upon no terms but an assumpsit.
"The Alchemist" by Ben Jonson
Stemming from it is "assumpsit", which provided damages for breach of an oral agreement and a written agreement without a seal.
"Our Legal Heritage, 5th Ed." by S. A. Reilly
Eodem tempore Jovinus ornatus regios assumpsit.
"Observations upon the Prophecies of Daniel, and the Apocalypse of St. John" by Isaac Newton
These are Assumpsit and Trover.
"Blackwood's Edinburgh Magazine, Volume 58, No. 359, September 1845" by Various
First, is the action of assumpsit.
"Putnam's Handy Law Book for the Layman" by Albert Sidney Bolles

In poetry:

Whereas, said the Plaintiffs, you owe us our living
By assumpsit implied, and the costs you must give in —
You have cheated us out of our bread and our butter,
Et alia enormia, too numerous to utter.
"Scire Facias" by John Gardiner Calkins Brainard