(かい)

かい
counter
floors, stories
1. floors, stories (of a building)
A counter for floors or stories of a building.
My room is on the fifth floor.
What floor are you going to?
(いっ)(かい)トイレあります
There is a restroom on the first floor.
いっかい with small っ
Let's take the elevator to the tenth floor.
The reception is on the second floor, but the meeting room is on the fifth floor.

(かい) is the counter for building floors and stories.

IRREGULAR READINGS:

  • (いっ)(かい): first floor (with っ)
  • (さん)(がい): third floor (voiced が)
  • (なん)(がい): what floor? (voiced が)

COUNTING:

  • ()(かい), (よん)(かい), ()(かい), (ろっ)(かい), (なな)(かい), (はっ)(かい)/(はち)(かい), (きゅう)(かい), (じゅっ)(かい)

JAPANESE VS. BRITISH ENGLISH:
The first floor in Japan ((いっ)(かい)) corresponds to the ground floor in British English. There is no separate 'ground floor' and 'first floor' distinction as in British usage.