Someone asks: Is “eight-year-old” hyphenated?

JG says: Yes, eight-year-old is hyphenated. Here’s why.

The words have to be linked closely together. The hyphen does that. Get rid of one link, and the phrase falls apart. For example–

eight year-old  turns “year-old” into a phrase, which it is not.
eight-year old  turns “old” into a noun, which it is not
eight year old   is just three words, not a phrase

eight-year-old is a phrase of three closely related words with “eight” modifying “year” and “eight” and “year” together modifying “old” and turning it into a noun.

So we hyphenate as follows:

an old woman eighty-five years old
a seventy-three-year-old man
A 60-mph speed limit
A five-time first-place winner

The one-hundred-year-old gentleman
or…The hundred-year-old gentleman

A 24-hour sale  (the noun that is being modified does not need a hyphen)

A 9-to-5 job

Have fun!

Joyce Griffith, MBA  Griffith Publishing