busy signal

American  

noun

1. Telephony. a regular succession of buzzing tones transmitted to a caller to indicate that the circuit serving the number is blocked or in use, rapid repetition indicating that the network is blocked and normal repetition that the telephone being called is in use.

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busy signal British  

noun

1. Also called (especially in Britain): engaged tone.  a repeated single note heard on a telephone when the number called is already in use

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Etymology

Origin of busy signal

First recorded in 1890–95

Example Sentences

The hours are limited and you often get the app equivalent of a busy signal.

From The Wall Street Journal • May 29, 2026

Calls to La Colombe’s five Chicago locations landed one Wi-Fi “yes,” two “noes,” one recurring busy signal, and one “no more indoor seating.”

From Slate • Jun. 4, 2024

He gets a busy signal from the shelter in North Hollywood and discovers with a Google search that it’s permanently closed.

From Los Angeles Times • Jul. 23, 2023

Instead, the deputies got a tone that was the equivalent of a busy signal.

From Seattle Times • Jun. 23, 2023

Behind her, a busy signal buzzed from the abandoned receiver.

From "Eleven" by Tom Rogers