(くう)

くう
prefix
empty; air; sky
weather
1. empty; vacant; blank
Prefix indicating emptiness or lack of content.
I'd like to make a reservation if there are empty seats.
(くう) + (せき) = empty seat
I like indulging in daydreams.
(くう) + (そう) = fantasy/daydream
Are there any vacant rooms?
2. air; sky; aerial
Prefix relating to air, sky, or aviation.
I'll go to pick you up at the airport.
(くう) + (こう) = airport
They showed a technique of spinning in midair.

(くう)〜 is a versatile prefix with meanings related to 'empty' or 'air/sky.'

Common compounds (EMPTY)

Common compounds (AIR/SKY)

Usage

The kanji (そら) means 'sky' when read as a standalone word, but takes the reading くう in many compounds.

Related Words