While the exact years that one enters middle age is uncertain, the spelling is very definite.
Middle age, a noun that means someone is about 40 to 65 years old, is two words (like ice cream) with no hyphen. For example: At the end of middle age, most people’s children have left home.
When using the word as an adjective – such as middle-aged – the hyphen appears, though. For example: Los Angeles has many middle-aged singles bars.
And with that, we can retire the issue of spelling of these two words for good.
My name is Rob Bignell. I’m an affordable, professional editor who runs Inventing Reality Editing Service, which meets the manuscript needs of writers both new and published. I also offer a variety of self-publishing services. During the past decade, I’ve helped more than 300 novelists and nonfiction authors obtain their publishing dreams at reasonable prices. I’m also the author of the 7 Minutes a Day… writing guidebooks, four nonfiction hiking guidebook series, and the literary novel Windmill. Several of my short stories in the literary and science fiction genres also have been published.