Dictionary.com
definitions

t-

  1. Chemistry. tertiary.

T-

  1. U.S. Military. (in designations of aircraft) trainer: T-11.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for t-

T-

abbreviation for
  1. trainer (aircraft)T-37
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