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1520s as a Latin word, nativized by 1590s, from Latin comma "short phrase," from Greek komma "clause in a sentence," literally "piece which is cut off," from koptein "to cut off," from PIE root *kop- "to beat, strike" (see hatchet (n.)). Like colon (n.1) and period, originally a Greek rhetorical term for a part of a sentence, and like them it has been transferred to the punctuation mark that identifies it.
A punctuation mark (,) used to indicate pauses and to separate elements within a sentence. “The forest abounds with oak, elm, and beech trees”; “The bassoon player was born in Roanoke, Virginia, on December 29, 1957.”
"," ASCII character 44. Common names: ITU-T: comma. Rare: ITU-T: cedilla; INTERCAL: tail.
In the C programming language, "," is an operator which evaluates its first argument (which presumably has side-effects) and then returns the value of its second argument. This is useful in "for" statements and macros.
in music, slight difference in frequency (and therefore pitch) occurring when a note of a scale, say E in the scale of C, is derived according to different systems of tuning. There are two commonly cited commas, the Pythagorean comma and the comma of Didymus, or syntonic comma