かい
kai

Noun
Suffix

1. storey; story; floor

それはもう ひと した きざはしですよ。
sorewa mō hitotsukano kaidesuyo
That's one level down.
Noun

2. stairs

わたくし部屋 へや よん かいにあります。
watashino heyawa yonkaini arimasu
My apartment is on the fourth floor.
Noun
Suffix

3. stage (in chronostratigraphy)

Counter

4. counter for storeys and floors of a building