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definitions

tab

1
[tab]
See more synonyms for tab on Thesaurus.com
noun
  1. a small flap, strap, loop, or similar appendage, as on a garment, used for pulling, hanging, or decoration.
  2. a tag or label.
  3. a small projection from a card, paper, or folder, used as an aid in filing.
  4. Informal. a bill, as for a meal in a restaurant; check.
  5. a small piece attached or intended to be attached, as to an automobile license plate.
  6. a small flap or tongue of material used to seal or close the opening of a container.
  7. Also called tabulator, tab key. a key on a typewriter that moves the carriage, typing element, etc., a predetermined number of spaces, used for typing text in columns, for fixed indentations, etc.
  8. Also called tab key. a key on a computer keyboard that moves the cursor a predetermined number of spaces, used for keying text in columns or form fields, for fixed indentations, etc.
  9. Digital Technology.
    1. (in a web browser window or in a spreadsheet or other application) a page displayed by clicking on or selecting a user interface element that resembles a paper tab:The third tab in the spreadsheet list expenses.
    2. the display of this user interface element:I have too many tabs open in my browser right now.
  10. Theater.
    1. a small, often narrow, drop curtain, for masking part of the stage.
    2. tableau curtain.
  11. Aeronautics. a small airfoil hinged to the rear portion of a control surface, as to an elevator, aileron, or rudder.Compare trim tab.
verb (used with object), tabbed, tab·bing.
  1. to furnish or ornament with a tab or tabs.
  2. to name or designate.
verb (used without object), tabbed, tab·bing.
  1. to operate the tab function on a typewriter or computer.
Idioms
  1. keep tabs/tab on, Informal. to keep an account of; check on; observe: The police kept tabs on the suspect's activities.

Origin of tab

1
1600–10; most senses of unknown origin;in def 7 short for tabulator; in def 10 short for tableau; in defs 4, 15 short for table
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

Related Words for keep tabs on

feed, nourish, vaccinate, cradle, do, protect, manage, watch, maintain, cultivate, keep, stare, listen, look, attend, scan, regard, see, observe, scrutinize
British Dictionary definitions for keep tabs on

tab

1
noun
  1. a small flap of material, esp one on a garment for decoration or for fastening to a button
  2. any similar flap, such as a piece of paper attached to a file for identification
  3. a small auxiliary aerofoil on the trailing edge of a rudder, aileron, or elevator, etc, to assist in the control of the aircraft in flightSee also trim tab
  4. British military the insignia on the collar of a staff officer
  5. mainly US and Canadian a bill, esp one for a meal or drinks
  6. Scot and Northern English dialect a cigarette
  7. keep tabs on informal to keep a watchful eye on
verb tabs, tabbing or tabbed
  1. (tr) to supply (files, clothing, etc) with a tab or tabs

Word Origin for tab

C17: of unknown origin

tab

2
noun
  1. short for tabulator, tablet
  2. slang a portion of a drug, esp LSD or ecstasy

TAB

abbreviation for
  1. typhoid-paratyphoid A and B (vaccine)
  2. Australian and NZ Totalizator Agency Board
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
Word Origin and History for keep tabs on

tab

n.1

"small flap," c.1600, possibly a dialectal word, of uncertain origin. Often interchangeable with tag (n.1). Cf. also Middle English tab "strap or string" (mid-15c.), Norwegian dialectal tave "piece of cloth, rag."

tab

n.2

"account, bill, check," 1888, American English colloquial, probably a shortened form of tabulation or of tablet in the sense of "a sheet for writing on." Figurative phrase keep a tab on is recorded from 1890.

tab

n.3

1961, shortened form of tablet (especially one of sugar containing LSD). As an abbreviation of tabloid (newspaper) it is 1990s slang. As a short form of tabulator key of a typewriter (later computer) it is recorded from 1916.

tab

v.

"to designate, label," 1924, perhaps an alteration of tag (v.2). Related: Tabbed; tabbing.

Online Etymology Dictionary, © 2010 Douglas Harper
Idioms and Phrases with keep tabs on

keep tabs on

Observe carefully, keep a record of. For example, I hate having my boss keep tabs on my every move, or We've got to keep tabs on outgoing mail so we can keep track of postage. This expression uses to tab in the sense of “an account.” [Late 1800s] Also see keep track.

tab

see keep tabs on.

The American Heritage® Idioms Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.