I wanted to use "middle-aged" in a sentence, and, curious whether the most frequest use was hyphenated or not, I looked it up on OneLook and saw it gave 17 links to dictionary definitions. It also gives a link, "See middle age for more definitions". That also gives 17 links.

What amused me, though, was that "middle age" is defined as "the time of life between youth and old age (e.g., between 40 and 60 years of age)", whereas "middle-aged (with hyphen) is shown as "being roughly between 45 and 65 years old".

By the way, "middleaged" (one word) only seems to appear in one dictionary.

This message has been edited. Last edited by: arnie,

Sort of goes with the general observation, oft broken, that the adjective is hyphenated, while the compound noun is not.

I used to teach a course on the middle-aged adult (generativity vs. stagnation is the developmental stage). Our age limits were 45-65.