From Middle High German *gelegenheit*, meaning "circumstances" or "situation," derived from *gelegen* ("situated, convenient") — past participle of *liegen* ("to lie, to be located") — plus the abstract suffix *-heit*. The semantic shift from "the way things lie" to "a favorable moment" mirrors the English evolution of "opportunity" from Latin *opportunus* ("at the port," i.e., a favorable wind).

Germans often use the proverb *"Gelegenheit macht Diebe"* — literally "opportunity makes thieves" — equivalent to the English "opportunity makes a thief." The word also appears in the common phrase *bei Gelegenheit* ("when you get a chance / sometime"), a relaxed way to suggest something without urgency. Don't confuse *Gelegenheit* with *Möglichkeit* ("possibility/option") — *Gelegenheit* stresses the right moment, while *Möglichkeit* stresses the mere ability to do something.