buzzer

Estimated CEFR level: C2 — Proficiency

Estimated from word frequency; not an official CEFR classification.

Definition

noun a push button at an outer door that gives a ringing or buzzing signal when pushed
noun a signaling device that makes a buzzing sound

From buzz + -er.

A buzzer sounded gently on Ethel K'wang-Li's desk. — Lone Star Planet, H. Beam Piper
He rang the buzzer for Mr. Adolph Meyers. — Blue-grass and Broadway, Maria Thompson Daviess
That was the Garrison house.” Babbitt sounded the buzzer. — Babbitt, Sinclair Lewis

doorbell, bell

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