the word 'trend' originates from the old english verb 'trendan', meaning "to turn, revolve, or roll." this verb is likely related to the middle high german 'trendel', meaning a circle or ring. the core concept of turning or rotating evolved metaphorically into the idea of a turning point or a bend in a course. by the late middle english period, it began to signify a general direction or inclination, particularly of a coastline. the modern abstract meanings, referring to a prevailing tendency in development or a popular style, solidified in the 19th and 20th centuries, capturing the sense of a figurative direction in which things are moving.

the word 'trend' is a simplex word of old english origin. it is not productively formed from smaller, independent morphemes in modern english.