Triarius may refer to:

• Triarius (tree), an 86.5-metre-high swamp gum Eucalyptus regnans in Tasmania
• Triarii, elements of early Roman military legions, consisting of wealthy and older man

• B&Q (retailer)
• B&Q Supercentre
• BQT
• B&Q Warehouse
• BR
• .br
• Br
• BR-101
• BR2
• BR.20
• BR-277
• BR3
• BR4
• BR5
• BR549
• BR6
• BR7
• BR8
• BR 92220 Evening Star
• BRA
• Braai
• Braaistand
• Braaivleis
• Braakman
• Braamfontein Werf