tab

American Heritage® Dictionary of the English Language, Fourth Edition

1. n. A projection, flap, or short strip attached to an object to facilitate opening, handling, or identification.
2. n. A small, usually decorative flap or tongue on a garment.
3. n. A small auxiliary airfoil that is attached to a larger one and that helps stabilize an aircraft.
4. n. A pull-tab.
5. v. To supply with a tab or tabs.
6. n. Informal A bill or check, such as one for a meal in a restaurant.
7. n. Informal Cost; price: The tab for upgrading the computers would be high.
8. n. A tabulator on a typewriter.
9. n. Computer Science 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.
10. n. Computer Science This special ASCII character.
11. v. To press the tab on a typewriter or computer keyboard: Tab over to the next column.
12. idiom. keep tabs on Informal To observe carefully: Let's keep tabs on expenditures.

Century Dictionary and Cyclopedia

1. n. A game something like backgammon, popular in Egypt and Palestine, played with four sticks.
2. n. 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. Specifically— A flap, strap, or latchet of a shoe.
3. n. Check; account: as, to keep tab on one.

Wiktionary

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

GNU Webster's 1913

1. n. The flap or latchet of a shoe fastened with a string or a buckle.
2. n. A tag. See Tag, 2.
3. n. A loop for pulling or lifting something.
4. n. A border of lace or other material, worn on the inner front edge of ladies' bonnets.
5. n. A loose pendent part of a lady's garment; esp., one of a series of pendent squares forming an edge or border.
6. n. 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.
7. n. a bill or check for some purchase, as in a restaurant.
8. n. 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.

WordNet 3.0

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