c. 1600, in logic, "setting forth a general principle by virtue of which a proposition must be true," from Late Latin ostensivus "showing," from Latin ostens-, past-participle stem of ostendere "to show" (see ostensible). Related: Ostensively.
ossuary
*ost-
osteitis
ostensible
ostensibly
ostensive
ostentation
ostentatious
osteo-
osteology
osteopath