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c.1400, "to interfere with a legal right," from Latin interruptus, past participle of interrumpere "break apart, break off," from inter- "between" (see inter-) + rumpere "to break" (see rupture (n.), and compare corrupt). Meaning "to break into (a speech, etc.)" is early 15c. Related: Interrupted; interrupting.
1957, originally in computers, from interupt (v.).