Vocabulary What does 歳 (さい, sai) mean? 歳 (さい, sai) means ... years old; age (of) .... Quick factsReadingさいRomajisaiPart of speechcounter 歳さいsai... years old; age (of) ...1counter ... years old; age (of) ...Also written: 才Kanji in this word歳years of age; year