t \t\ t=e,
   the twentieth letter of the english alphabet, is a nonvocal
   consonant. with the letter h it forms the digraph th, which
   has two distinct sounds, as in thin, then. see guide to
   pronunciation, sectsect262-264, and also sectsect153,
   156, 169, 172, 176, 178-180.
   1913 webster the letter derives its name and form from the
   latin, the form of the latin letter being further derived
   through the greek from the phoenician. the ultimate origin
   is probably egyptian. it is etymologically most nearly
   related to d, s, th; as in tug, duke; two, dual, l. duo;
   resin, l. resina, gr. "rhti`nh, tent, tense, a., tenuous,
   thin; nostril, thrill. see d, s.
   1913 webster

   t bandage surg., a bandage shaped like the letter t, and
      used principally for application to the groin, or
      perineum.

   t cart, a kind of fashionable two seated wagon for pleasure
      driving.

   t iron.
   a a rod with a short crosspiece at the end, -- used as a
       hook.
   b iron in bars, having a cross section formed like the
       letter t, -- used in structures.

   t rail, a kind of rail for railroad tracks, having no
      flange at the bottom so that a section resembles the
      letter t.

   t square, a ruler having a crosspiece or head at one end,
      for the purpose of making parallel lines; -- so called
      from its shape. it is laid on a drawing board and guided
      by the crosspiece, which is pressed against the straight
      edge of the board. sometimes the head is arranged to be
      set at different angles.

   to a t, exactly, perfectly; as, to suit to a t. colloq.
      1913 webster
see also:
d s t bandage t cart t iron t rail 
t square to a t