tab

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun A tabloid.
• noun A bill or check, such as one for a meal in a restaurant.
• noun Cost; price.
• noun A tabulator on a typewriter.
• noun A key on a computer keyboard that, when pressed, inserts a special ASCII character used for formatting text, as in indenting a line or block of text.
• noun This special ASCII character.
• intransitive verb To press the tab on a typewriter or computer keyboard.
• idiom (keep tabs on) To observe carefully over time.
• noun A projection, flap, or short strip attached to an object to facilitate opening, handling, or identification.
• noun A small, usually decorative flap or tongue on a garment.
• noun A small auxiliary airfoil that is attached to a larger one and that helps stabilize an aircraft.
• noun A pull-tab.
• transitive verb To supply with a tab or tabs.

from The Century Dictionary.

• noun A small flap, strap, or strip of some material made fast to an object at one end or side, and either free or fastened at the other when in use, as in a garment; a tag.
• noun Check; account: as, to keep tab on one.
• noun A game something like backgammon, popular in Egypt and Palestine, played with four sticks.

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

• noun The flap or latchet of a shoe fastened with a string or a buckle.
• noun A tag. See Tag, 2.
• noun A loop for pulling or lifting something.
• noun A border of lace or other material, worn on the inner front edge of ladies' bonnets.
• noun A loose pendent part of a lady's garment; esp., one of a series of pendent squares forming an edge or border.
• noun a small projecting piece of a file folder, file card, or similar sheet used in a filing system, on which a notation is written to permit convenient search for the folder, card, etc.
• noun a bill or check for some purchase, as in a restaurant.
• noun a key on a typewriter or computer keyboard which advances the carriage or curser to the next (preset) tab position; -- used especially to type or print text or numbers in columns.

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

• noun A form of musical notation indicating fingering rather than the pitch of notes, commonly used for stringed instruments.
• noun informal A restaurant bill.
• noun slang Credit account, e.g., in a shop or bar.
• noun Short for tabulator.
• noun computing A space character (     ) that extends to the next aligned column, traditionally used for tabulation.
• noun A small flap or strip of material attached to something, for holding, manipulation, identification, etc.
• noun by extension (graphical user interface) A navigational widget for switching between sets of controls or documents.
• noun informal A tablet, especially one containing illicit drugs.
• noun British Army, slang A fast march or run with full kit.
• noun slang A student of Cambridge University, derived from the Latin Cantabrigia (often shortened to Cantab.).
• verb Mark with a tab.
• verb computing To use the Tab key on a computer or typewriter to navigate the screen or page.
• verb Short for tabulate.
• noun Geordie cigarette.

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

• noun the bill in a restaurant
• noun sensationalist journalism
• noun a dose of medicine in the form of a small pellet
• noun a short strip of material attached to or projecting from something in order to facilitate opening or identifying or handling it
• noun the key on a typewriter or a word processor that causes a tabulation