HYPOTH'ESIS, noun [Latin from Gr. a supposition; to suppose.] 1. A supposition; a proposition or principle which is supposed or taken for granted, in order to draw a conclusion or inference for proof of the point in question; something not proved, but assumed for the purpose of argument. 2. A system or theory imagined or assumed to account for what is not understood.
Source: Webster's 1828 American Dictionary ↗ · public-domain · returned verbatim, no AI