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space; room; gap; emptiness
vacancy; opening; empty seat
free time; time to spare
disuse; unused thing
棚に明きがあるから荷物を置ける。
There's space on the shelf, so we can put the luggage there.
駐車場に明きがなくて困った。
There was no empty spot in the parking lot.
明きがないので座れません。
There's no room, so I can't sit.