godan verb (-ku), intransitive verb
become less crowded; thin out; get empty
Describes a space, vehicle, or container becoming less full or empty. Often used for trains, restaurants, or streets.
電車が空いてきた。
The train has become less crowded.
この時間はレストランが空いている。
The restaurant is not crowded at this time.
godan verb (-ku), intransitive verb
Used in the fixed expression お腹が空く (or 腹が空く) to mean 'get hungry'. Not used alone for hunger.
See also: お腹が空く
お腹が空いたので、何か食べたい。
I'm hungry, so I want to eat something.