Collins English-English Dictionary

tab [tæb]

1. 1. n a small flap of material, esp one on a garment for decoration or for fastening to a button

2. 2. n any similar flap, such as a piece of paper attached to a file for identification

3. 3. n a small auxiliary aerofoil on the trailing edge of a rudder, aileron, or elevator, etc, to assist in the control of the aircraft in flight - See also trim tab

4. 4. n [Brit] [military] the insignia on the collar of a staff officer

5. 5. n [chiefly US and Canadian] a bill, esp one for a meal or drinks

6. 6. n [Scot and northern English] [dialect] a cigarette

7. 7. vt. [tr] to supply (files, clothing, etc) with a tab or tabs

8. 8. vt. [Etymology] C17: of unknown origin

tab [tæb]

1. 1. n short for tabulator

2. 2. n [slang] a portion of a drug, esp LSD or ecstasy