"relating to or having experience, derived from experience, empirical," 1640s (implied in experientially), from Latin experientia "knowledge gained by testing or trials" (see experience (n.)) + -al (1).
late 14c., "observation as the source of knowledge; actual observation; an event which has affected one," from Old French esperience "experiment, proof, experience" (13c.), from Latin experientia "a trial, proof, experiment; knowledge gained by repeated trials," from experientem (nominative experiens) "experienced, enterprising, active, industrious," present participle of experiri "to try, test," from ex "out of" (see ex-) + peritus "experienced, tested," from PIE *per-yo-, suffixed form of root *per- (3) "to try, risk." Meaning "state of having done something and gotten handy at it" is from late 15c.
suffix forming adjectives from nouns or other adjectives, "of, like, related to, pertaining to," Middle English -al, -el, from French or directly from Latin -alis (see -al (2)).
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Definitions of experiential
relating to or resulting from experience;
a personal, experiential reality
derived from experience or the experience of existence; "the rich experiential content of the teachings of the older philosophers"- Benjamin Farrington; "formal logicians are not concerned with existential matters"- John Dewey;