'Suppose' is Latin for 'place under' — placing something beneath an argument as its unproven foundation.
To assume or believe something to be true without proof; to expect or require as a condition; used to make a tentative suggestion.
From Old French 'supposer' (to assume, to put under), a Romance remodeling of Latin 'suppōnere' (to place under, to substitute), from 'sub-' (under) and 'pōnere' (to put, to place). The literal meaning is 'to place under' — to put something as a foundation or basis underneath an argument. The semantic shift from 'placing under' to 'assuming' reflects the idea that a supposition is something placed under an argument as its unproven base. Key roots: pōnere / positum (Latin: "to put, to place"), sub- (Latin: "under, below, beneath").
The rare English word 'supposititious' (meaning fraudulently substituted) preserves the original Latin meaning of 'suppōnere' — to put one thing under or in place of another. A supposititious child was one secretly substituted for the real heir, a plotline beloved of Roman comedy and later Gothic fiction.
Words closest in meaning, ranked by similarity