pretension (n.)

mid-15c., pretensioun, "assertion, allegation; objection; intention; signification," from Medieval Latin pretensionem (nominative pretensio), noun of action from past-participle stem of Latin praetendere "stretch in front, put forward, allege" (see pretend (v.)).

Meaning "unproven claim" is from c. 1600. The sense of "ostentation" is from 1727, from the notion of "act of putting forth a (false) claim to merit, dignity, or importance."