(typography) The serial comma.

A comma preceding the final conjunction in a list of three or more items, especially to provide clarity.

(grammar) Two independent clauses combined into a run-on sentence with only a comma between them.

plural of comma splice

A punctuation mark, ⟨、⟩, used in Chinese, Japanese, Korean, and other languages that use Chinese-derived ideographs, and which has a similar function to the comma in languages that use the Roman alphabet.

(rare, childish) An apostrophe.

(bacteriology) A variety of bacillus shaped like a comma, found in the intestines of patients suffering from cholera.

The Johannine Comma; a phrase included in some manuscripts of 1 John 5:7-8.

A short phrase, included in some manuscripts of 1 John 5:7-8, whose authenticity is debated and is widely agreed to be an interpolation.

plural of comma queen