See also: Trb. English Proper noun TRB (US) Initialism of Transportation Research Board. (Philippines) Initialism of Toll Regulatory Board. Noun TRB (uncountable) (military, firearms) Initialism of tap, rack, bang. Anagrams BRT, RBT, RTB, TBRWikiwand - on Seamless Wikipedia browsing. On steroids.Remove ads