[1680–90; tri- + petalous]This word is first recorded in the period 1680–90. Other words that entered Englishat around the same time include: commode, gangway, knockdown, skyrocket, turnofftri- is a combining form meaning “three,” used in the formation of compound words. Otherwords that use the affix tri- include: triforium, triglyph, trilemma, triple, trivial