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emptiness; being empty
not carrying anything; unburdened; empty-handed
dishonoured (bill, promise, etc.); false; no-show (reservation); put-on (cheeriness, courage, etc.); empty (compliments); insincere
「虚」 has other readings with different meanings.
虚の箱がそこにあったよ。
There was an empty box there.
瓶が虚になったら捨てよう。
Let's throw the bottle away when it's empty.
財布の中が虚っぽで何も買えなくて困った。
My wallet was empty and I couldn't buy anything — I was stuck.