colon

from The Century Dictionary.

• noun In ancient Grammar and rhetoric, one of the larger or principal divisions of a sentence or period; a long clause, or a group of minor clauses or commata. See comma, 1.
• noun In ancient prosody, one of the members or sections of a rhythmical period, forming an uninterrupted sequence of feet, united under a principal ictus or beat: sometimes called a series.
• noun In paleography, a long clause or group of clauses, or a series of words of about the average length of such a group, estimated as approximately equal to a dactylic hexameter in extent—that is, as containing from 12 to 17 syllables.
• noun A mark of punctuation formed by two dots like periods placed one above the other (:), used to mark a discontinuity of grammatical construction greater than that indicated by the semicolon and less than that indicated by the period.
• noun The silver peso or dollar of Costa Rica, of the value of 46½ cents or 100 centavos.
• noun In anatomy, a portion of the intestinal tract, the so-called “large” as distinguished from the “small” intestine, continuous from the ileum to the rectum; the great gut, beginning at the cæcum and ending in the sigmoid flexure.
• noun In entomology, the second portion of an insect's intestine, generally broader than the preceding portion or ileum.

from the GNU version of the Collaborative International Dictionary of English.

• noun (Anat.) That part of the large intestines which extends from the cæcum to the rectum. [See Illust. of digestion.]
• noun (Gram.) A point or character, formed thus [:], used to separate parts of a sentence that are complete in themselves and nearly independent, often taking the place of a conjunction.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun anatomy Part of the large intestine; the final segment of the digestive system, after (distal to) the ileum and before (proximal to) the anus
• noun grammar The punctuation mark ":".
• noun rare The triangular colon (especially in context of not being able to type the actual triangular colon).
• noun A rhetorical figure consisting of a clause which is grammatically, but not logically, complete.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun the part of the large intestine between the cecum and the rectum; it extracts moisture from food residues before they are excreted
• noun a punctuation mark (:) used after a word introducing a series or an example or an explanation (or after the salutation of a business letter)
• noun the basic unit of money in El Salvador; equal to 100 centavos
• noun a port city at the Caribbean entrance to the Panama Canal
• noun the basic unit of money in Costa Rica; equal to 100 centimos