ASSUMPSIT
Etymology
Noun
assumpsit (plural assumpsits)
(legal) A promise or undertaking, either express or implied, founded on a consideration.
(legal) An action to recover damages for breach or nonperformance of such a promise.
Source: Wiktionary
As*sump"sit, n. Etym: [L., he undertook, pret. of L. assumere. See
Assume.] (Law)
(a) 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.
(b) An action to recover damages for a breach or nonperformance of a
contract or promise, express or implied, oral or in writing not under
seal. Common or indebitatus assumpsit is brought for the most part on
an implied promise. Special assumpsit is founded on an express
promise or undertaking. Wharton.
Source: Webster’s Unabridged Dictionary 1913 Edition