What does suppositious mean?
Supposititious means based on an assumption rather than on established evidence or demonstrated fact. The word is especially associated with legal argument, logic, and philosophy, where it describes a case, proposition, argument, or condition introduced for the sake of analysis or hypothetical reasoning. A statement need not be false to be suppositious: what matters is that it is being treated as true under an imagined or assumed set of circumstances. The adjective can also carry the broader sense of merely presumed, particularly in older or formal usage. Its deliberately specialized character makes it useful when the distinction between an actual fact and a working assumption matters. In ordinary conversation, hypothetical or assumed will usually communicate the same idea more simply, but suppositious conveys a more precise and traditional vocabulary.
adjectiveBased on supposition rather than established fact; hypothetical or assumed. In legal and philosophical use, it may also mean merely presumed or imagined, especially when treated as if true.
- Based on supposition or assumption rather than demonstrated fact.
- Regarded as true for the sake of argument or inquiry; hypothetical.
"The court considered the claim under the supposititious premise that the contract had been validly signed."
"The experiment tested a suppositious relationship between temperature and plant growth."
"In law, the court distinguished between a supposititious case and one supported by evidence."
A suppositious proposition can be perfectly clear in logic while remaining entirely unproved in the real world.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Where does suppositious come from?
The word derives through Latin from supponere, a form of the Latin verb meaning “to place underneath” and, by extension, “to put forward” or “to suppose.” Its development also reflects supponere’s past participle, suppositus, meaning “placed underneath” or “put forward.” The English word entered through a Latin adjective in the family of suppositius or supposititius, with the meaning “supposed” or “assumed.” Cognates in English include suppose, supposition, supplement, and proposition, all reflecting forms of the same Latin root.
Related word forms
How suppositious is actually used
This is a formal and relatively uncommon word, encountered especially in law, logic, and philosophy. It is more pointed than hypothetical because it emphasizes the provisional status of an assumption or premise.
Easily confused with suppositious
Supposititious specifically characterizes something accepted only as an assumption or hypothetical condition, whereas supposed is the more general word for something believed or assumed to be the case.