An excess or surplus — something that is more than necessary or appropriate.
塩を過剰に使うと料理の味が台無しになる。
If you use too much salt, the dish's taste will be ruined.
過剰な期待はしばしば失望を招く。
Excessive expectations often lead to disappointment.
薬の過剰摂取は危険だ。
Overdosing on medicine is dangerous.