two-year-old
Meaning
being two years of age
a person or animal that is two years old
Usage
they have a lively two-year-old daughter.
the farm sold a two-year-old horse at the auction.
this toy is suitable for a two-year-old.
Etymology
The word "two-year-old" is a Modern English compound construction, following a straightforward pattern for indicating age. Its components are deeply rooted in the Germanic branch of the Indo-European family. "two" derives from Proto-Germanic twai, "year" from jērą, and "old" from aldaz. The logic of the compound is entirely transparent, directly combining these elemental concepts. The hyphenated form standardizes the phrase, transforming it into a single lexical unit that functions as either an adjective or a noun to specify age precisely.
Analysis
This is a compound adjective/noun formed by combining the numeral "two", the noun "year", and the adjective "old" with hyphens. Each element retains its core meaning from Old English: "twā" (two), "gēar" (year), and "eald" (old).