T
     n 1: a base found in DNA (but not in RNA) and derived from
          pyrimidine; pairs with adenine [syn: {thymine}]
     2: one of the four nucleotides used in building DNA; all four
        nucleotides have a common phosphate group and a sugar
        (ribose) [syn: {deoxythymidine monophosphate}]
     3: a unit of weight equivalent to 1000 kilograms [syn: {metric
        ton}, {MT}, {tonne}]
     4: a unit of information equal to a trillion
        (1,099,511,627,776) bytes or 1024 gigabytes [syn: {terabyte},
         {TB}]
     5: the 20th letter of the Roman alphabet
     6: thyroid hormone similar to thyroxine but with one less
        iodine atom per molecule and produced in smaller quantity;
        exerts the same biological effects as thyroxine but is
        more potent and briefer [syn: {triiodothyronine}, {liothyronine}]
     7: hormone produced by the thyroid glands to regulate
        metabolism by controlling the rate of oxidation in cells;
        "thyroxine is 65% iodine" [syn: {thyroxine}, {thyroxin}, {tetraiodothyronine}]
Source: WordNet® 2.0

T /T/ 1. [from LISP terminology for `true'] Yes. Used in reply to a
   question (particularly one asked using {The -P convention}). In LISP,
   the constant T means `true', among other things. Some Lisp hackers use
   `T' and `NIL' instead of `Yes' and `No' almost reflexively. This
   sometimes causes misunderstandings. When a waiter or flight attendant
   asks whether a hacker wants coffee, he may absently respond `T', meaning
   that he wants coffee; but of course he will be brought a cup of tea
   instead. Fortunately, most hackers (particularly those who frequent
   Chinese restaurants) like tea at least as well as coffee -- so it is not
   that big a problem. 2. See {time T} (also {since time T equals minus
   infinity}). 3. [techspeak] In transaction-processing circles, an
   abbreviation for the noun `transaction'. 4. [Purdue] Alternate spelling
   of {tee}. 5. A dialect of {LISP} developed at Yale. (There is an
   intended allusion to NIL, "New Implementation of Lisp", another dialect
   of Lisp developed for the {VAX})


Source: The Jargon File