four-year-old
UK: ˌfɔː jɪər ˈəʊld | US: ˌfɔr jɪr ˈoʊld
adj. describing something or someone that is four years in age
n. a person or animal that is four years old
The term "four-year-old" is a straightforward compound adjective/noun formed by combining the cardinal number "four," the unit of time "year," and the adjective "old." This structure follows a common English pattern for age designation (e.g., "five-year-old," "ten-year-old"). The hyphenation ensures clarity, treating the phrase as a single modifier. The logic is transparent: it literally means "having lived for four years."
The four-year-old child proudly showed her drawing to the class.
We adopted a four-year-old rescue dog from the shelter.
This toy is designed for four-year-olds.
The four-year-old car still runs smoothly.
Her four-year-old brother started kindergarten this fall.