[1750–60; tri- + -phyllous]This word is first recorded in the period 1750–60. Other words that entered Englishat around the same time include: Yankee, bunker, infiltrate, quartz, railroadtri- is a combining form meaning “three,” used in the formation of compound words. Otherwords that use the affix tri- include: trigeminal, trilemma, trinomial, trio, triple; -phyllous is a combining form meaning “having leaves” of the kind or number specified by theinitial element. Other words that use the affix -phyllous include: anisophyllous, chylophyllous, gamophyllous, heterophyllous, stenophyllous