advenir

Advenir means to happen or come to pass — a literary, formal register for arriver or se produire, and grammatically defective: it's used mainly in the infinitive, the third person, and the past participle (advenu), almost never conjugated for je/tu/nous/vous.

• Quoi qu'il advienne, je resterai à tes côtés. — Whatever happens, I'll stay by your side.
• Nul ne sait ce qu'il adviendra de ce projet. — No one knows what will become of this project.
• Advienne que pourra, nous partons demain. — Come what may, we're leaving tomorrow.

Learners try to conjugate advenir fully like a regular -enir verb ("j'adviens", "tu adviens") — but it's a defective, largely impersonal verb, essentially restricted to il advient / il adviendra / advenu, and to the fixed formula "advienne que pourra."

Often confused with arriver.

• expression Advienne que pourra — A fixed 16th-century expression built directly on this verb, an ellipsis of "advienne ce qui pourra" ("come what may"/"whatever happens, happens"), still in everyday use as a statement of fatalistic acceptance.