comma

[kom-uh] /ˈkɒm ə/
noun
1.
the sign (,), a mark of punctuation used for indicating a division in a sentence, as in setting off a word, phrase, or clause, especially when such a division is accompanied by a slight pause or is to be noted in order to give order to the sequential elements of the sentence. It is also used to separate items in a list, to mark off thousands in numerals, to separate types or levels of information in bibliographic and other data, and, in Europe, as a decimal point.
2.
Classical Prosody.
  1. a fragment or smaller section of a colon.
  2. the part of dactylic hexameter beginning or ending with the caesura.
  3. the caesura itself.
3.
Music. the minute, virtually unheard difference in pitch between two enharmonic tones, as G♯ and A♭.
4.
any of several nymphalid butterflies, as Polygonia comma, having a comma-shaped silver mark on the underside of each hind wing.
Origin
1520-30; < Late Latin: mark of punctuation, Latin: division of a phrase < Greek kómma piece cut off (referring to the phrase so marked), equivalent to kop- (base of kóptein to strike, chop) + -ma noun suffix denoting result of action (with assimilation of p)
British Dictionary definitions for commas

comma

/ˈkɒmə/
noun
1.
the punctuation mark(,) indicating a slight pause in the spoken sentence and used where there is a listing of items or to separate a nonrestrictive clause or phrase from a main clause
2.
(music) a minute interval
3.
short for comma butterfly
Word Origin
C16: from Latin, from Greek komma clause, from koptein to cut
Word Origin and History for commas

comma

n.

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.

commas in Culture

comma definition


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.”

Encyclopedia Article for commas

comma

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

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