The number zero (0); the concept of none or nil used in mathematics and everyday contexts.
外の気温は0度だった。
The outside temperature was 0 degrees.
試合は3対0で勝った。
The match was won three to zero.
その商品の在庫は0になった。
The stock of that item became zero.
Colloquial/figurative use meaning 'nothing' or 'zilch' (often written in kana or as the digit 0).
最近、やる気が0で何も手につかない。
Lately my motivation has been zero and I can't get anything done.
彼の貢献はほとんど0に等しいと言える。
One could say his contribution is almost zero.