comma
noun
- 3 (also comma butterfly) a butterfly that has wings with irregular, ragged edges and typically a white or silver comma-shaped mark on the underside of each hind wing.
- Genus Polygonia, subfamily Nymphalinae, family Nymphalidae: numerous species, in particular the common eastern comma (P. comma) of eastern North America
Origin:
late 16th century (originally as a term in rhetoric denoting a group of words shorter than a colon; see colon1): via Latin from Greek komma 'piece cut off, short clause', from koptein 'cut'
Grammar
This punctuation mark has the following uses: to separate the items in a list:... tens of thousands of them: Christians, Hindus, Muslims, Sikhs. to set off a parenthetical section of a sentence (as parentheses do):Bill the dog, happy as ever to be out and about, was sniffing everything in sight. to mark the divisions between the clauses in a complex sentence:These weedkillers may, if used on new lawns, damage young seedling grasses before they are well established. to separate sections of a sentence to make it easier to read:To make a hot compress, pour hot water into a bowl and then add the essential oil. to introduce and/or end a piece of direct speech:“No, sir,” said Stephen, “and that is what is so curious.” You do not need to use a comma between nouns that are in apposition:my wife Dorothy Alison and her friend Beth were attracted to the same man at a party. Commas should be used to surround a noun that is parenthetical:Pete, his son, cleaned the garden aviary. Use a comma when writing a number that is made up of four or more figures:23,500 1,500 miles but not in dates:May 2004 the 1970s