also: からばこ
noun
empty box
A box that is empty; can refer to any kind of box (cardboard, wooden, etc.) that no longer contains anything.
引っ越しの後、空き箱がたくさん残った。
After moving, a lot of empty boxes were left.
その空き箱は捨ててもいいですか。
Is it okay to throw away that empty box?
Kanji-only spelling, often read からばこ. Can also be read あきばこ, but 空き箱 is preferred for that reading.
Possible but uncommon reading for this kanji form; 空き箱 is the usual spelling for あきばこ.
空っぽ is an adjective meaning 'empty' in general, while 空き箱 specifically refers to an empty box.
Compound of 空き (aki, 'empty') or 空 (kara, 'empty') + 箱 (hako, 'box'). The reading あきばこ is more common in modern Japanese.