definition of a colon
Noun. 1. colon-the part of the large intestine between the cecum and the rectum; it extracts moisture from food residues before they are excreted. sigmoid vein, vena sigmoideus-tributaries of the inferior mesenteric vein; drains the sigmoid colon.
5. colon-a punctuation mark (:) used after a word introducing a series or an example or an explanation (or after the salutation of a business letter). punctuation mark, punctuation-the marks used to clarify meaning by indicating separation of words into sentences and clauses and phrases. Translations.