How do you say fast in Japanese?
— 速い; はやい (hayai)

Similar to for fast in Japanese
hot熱い (あつい, atsui)
Category relationships for fast in Japanese
music音楽 (おんがく, ongaku)
Antonyms for fast in Japanese
slow遅い (おそい, osoi); ゆっくり (yukkuri); 鈍足 (どんそく, donsoku)