Ob*ver"sion (?), n. [L. obversio a turning towards.]
1.
The act of turning toward or downward.
2. Logic
The act of immediate inference, by which we deny the opposite of anything which has been affirmed; as, all men are mortal; then, by obversion, no men are immortal. This is also described as "immediate inference by privative conception."
Bain.
© Webster 1913.