1610s, "of or pertaining to an institution," from institution + -al (1). Related: Institutionally.
Entries linking to institutional
institution n.
c. 1400, "action of establishing or founding (a system of government, a religious order, etc.)," from Old French institucion "foundation; thing established" (12c.), from Latin institutionem (nominative institutio) "a disposition, arrangement; instruction, education," noun of state from institutus (see institute (v.)).
Meaning "established law or practice" is from 1550s. Meaning "establishment or organization for the promotion of some charity" is from 1707. Jocular or colloquial use for "anything that's been around a long time" is from 1837.
-al 1
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)).