Bt ['bē-'tē] -n

  1. a preparation of a bacterium ( Bacillus thuringiensis) often modified by genetic engineering for use as a biopesticide against insects and esp. lepidopteran larvae
  2. the bacterium itself
  3. baronet

btry -abbr

  1. battery

Btu [,bē-,tē-'yü] -n

  1. british thermal unit

BTW -abbr

  1. by the way