Morse code

American  

noun

1. either of two systems of clicks and pauses, short and long sounds, or flashes of light, used to represent the letters of the alphabet, numerals, etc.: now used primarily in radiotelegraphy by ham operators.

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Morse code British  

noun

1. Also called: international Morse code.  a telegraph code formerly used internationally for transmitting messages; it was superseded by satellite technology (the Global Marine Distress and Safety System) in 1999. Letters, numbers, etc, are represented by groups of shorter dots and longer dashes, or by groups of the corresponding sounds, dits and dahs, the groups being separated by spaces

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Morse code Scientific  

1. A code developed by Samuel Morse used for transmitting messages in which letters of the alphabet and numbers are represented by various sequences of written dots and dashes, or short and long signals such as electric tones or voltages. Morse code was used extensively in telegraphy. In a format that has been standardized for international use, it is still sometimes used for long distance radio communication.

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Etymology

Origin of Morse code

First recorded in 1830–40; after S. F. B. Morse

Example Sentences

After divorcing her husband, she was posted to RAF Gibraltar where she worked as a telegraphist, a job which saw her work with morse code and given high level security clearance.

From BBC • Oct. 27, 2025

Perhaps the message was hinting at the aliens’ appearance, morse code, cellular automata or the genetic secrets of E.T.

From Scientific American • Aug. 3, 2023

They flash like morse code messages from childhood, the Tinkerbells of the longest days of summer.

From Seattle Times • Jul. 29, 2023

One method he dubbed “ETHERLED” turns a secure computer’s blinking LED lights into morse code to transmit data from the secure computer.

From Washington Times • Aug. 29, 2022

Public interest remains unabated in the remarkable occurrences at the poultry-house farm at Brickendon, where spirit rappings in the morse code have been heard for weeks past....

From Punch, or the London Charivari, Vol. 158, 1920-02-11 by Various