Etymology
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Morse code (n.)

character encoding system originally invented for use with the telegraph, by 1860, earlier Morse key (1858), so called in honor of Samuel F.B. Morse (1791-1872), U.S. inventor who produced a system of telegraphic communication in 1836. He invented both the recording telegraph and the alphabet of dots and dashes.

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code (v.)

"to put into code," 1815, from code (n.). Specifically "to put into computer code" from 1947. Intransitive sense "write computer code" is by 1987. Related: Coded; coding.

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code (n.)

c. 1300, "systematic compilation of laws," from Old French code "system of laws, law-book" (13c.), from Latin codex"systematic classification of statutory law," earlier caudex "book," literally "tree trunk," hence, book made up of wooden tablets covered with wax for writing. De Vaan traces this through Proto-Italic *kaud-ek- to PIE *kehu-d- "cleaved, separate," which he also sees as the root of cauda "tail" (see coda).

Meaning "cipher, system of signals and the rules which govern their use" (the sense in secret code) is from 1808. Code-name is from 1879 (in telegraphy). Meaning "system of expressing information and instructions in a form usable by a computer" is from 1946.

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black code (n.)
local or state legal restrictions on black persons, free or slave, 1774, American English, though the first reference is to French colonies in the West Indies.
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umpty 
1905, "of an indefinite number," originally Morse code slang for "dash," influenced by association with numerals such as twenty, thirty, etc.
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POTUS (n.)

wire service acronym for president of the United States (or President of the United States). It is a survival from the Phillips Code, created 1879 by U.S. journalist Walter P. Phillips to speed up (and save money on) Morse code transmissions but obsolete from c. 1940 with the widespread use of teletype machines. The AP still uses it in wire slugs and it is affected occasionally by those seeking to establish journalistic credibility. Other Phillips Code survivals include SCOTUS for "Supreme Court of the United States."

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dash (n.)

late 14c., "a violent striking together of two bodies," from dash (v.). In writing and printing, "horizontal line used as a punctuation mark," 1550s. Meaning "small infusion or mixture" is from 1610s. Meaning "showy appearance" is from 1715; sense of "capacity for prompt action" is by 1796. As one of the two Morse code signals from 1859. Sporting sense is from 1881, originally "a short race run in one attempt, not in heats."

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SOS 
1910, from International Morse code letters, chosen arbitrarily as being easy to transmit and difficult to mistake. Not an initialism (acronym) for "save our ship" or anything else. Won out over alternative suggestion C.Q.D., which is said to mean "come quickly, distress," or "CQ," general call for alerting other ships that a message follows, and "D" for danger. SOS is the telegraphic distress signal only; the oral equivalent is mayday.
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codify (v.)

"to reduce to a code or digest, to arrange or systematize," c. 1800 (Bentham), from code (n.) + -ify. Related: codified; codifying.

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encode (v.)
1917, from en- (1) "make, put in" + code (n.). Computing sense is from 1955, usually shortened colloquially or for clarity to code. Related: Encoded; encoding.
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