歳
Kana: さい
years old
Example sentence
弟は五歳です。
おとうとはごさいです。
My little brother is five years old.
What 歳 means
歳 (さい) is a Japanese word meaning “years old”. It belongs to the Numbers & Measure topic and appears at Level 1, so it is one of the words worth learning early when you study Japanese.