emptiness

1. N-UNCOUNT A feeling of emptiness is an unhappy or frightening feeling that nothing is worthwhile, especially when you are very tired or have just experienced something upsetting. 空虛

The result later in life may be feelings of emptiness and depression. 結果是往後的生活可能會感到空虛和沮喪。

2. N-UNCOUNT The emptiness of a place is the fact that there is nothing in it. 空曠

...the emptiness of the desert. …沙漠的空曠。