A Quick and Simple Dictionary

tan

1. (initialism) .  (engineering) '''T'''otal '''A'''cid '''N'''umber, the measure of a lubricant's or crude oil's acidity.
2. (initialism) .  (banking) '''T'''ransaction '''a'''uthentication '''n'''umber, in electronic banking.
3. (initialism) .  IATA airport code for Taunton Municipal Airport in Taunton, Massachusetts.
4. Proper noun.  An English surname derived from the transliteration of various Asian surnames, particularly originating from China and Vietnam.
5. Noun.  A yellowish-brown colour.
6. Noun.  A darkening of the skin resulting from exposure to sunlight or similar light sources.
7. Noun.  The bark of an oak or other tree from which tannic acid is obtained.
8. Adjective.  Of a yellowish-brown.
9. Adjective.  Having dark skin as a result of exposure to the sun.
10. Verb.  (intransitive) To change to a tan colour due to exposure to the sun.
11. Verb.  (transitive) To change an animal hide into leather by soaking it in tannic acid.See Wikipedia article on Tanning. To work as a tanner.
12. Verb.  (transitive, informal) To spank or beat.
13. Cardinal number.  (dialect, rare) The second cardinal number two, formerly used in Celtic areas, especially Cumbria and parts of Yorkshire, for counting sheep, and stitches in knitting.See Wikipedia article on Yan Tan Tethera.