[1810–20; tri- + cornered]This word is first recorded in the period 1810–20. Other words that entered Englishat around the same time include: dominance, dynamic, nihilism, voodoo, zombietri- is a combining form meaning “three,” used in the formation of compound words. Otherwords that use the affix tri- include: triathlon, triglyceride, trinomial, triple, trivial