1680s, "pertaining to disease," formed in English from pathologic + -al (1). Sense of "worthy to be a subject of pathology, morbid, excessive" (as in pathological liar) is attested from 1845. Related: Pathologically.
"pertaining to pathology, of or pertaining to disease," 1650s, perhaps modeled on French pathologique; see pathology + -ic.
a pathological urge to succeed
a pathological liar
pathological bodily processes