In Chinese, young people are sometimes referred to as ken lao zu—“the generation that eats the old.” In Swedish, they are the curlingbarn—a name taken from the popular winter sport of curling, in which two sweepers clear a path in front of a puck so that it glides smoothly along the ice. The allusion is an amusing one: Like the puck, young people today have had their paths swept smooth by doting parents.

There are various neologisms used in the English language to describe millennials, most of them negative. They have been branded the “selfie generation,” a label that ostensibly references a love of posting pictures online (one recent study suggested that the average millennial will take 25,000 selfies in their lifetime). But the term also conveys a sense of unseemly self-ob...