ichidan verb, transitive verb
Used when someone does something to an excessive degree; often attached to the continuative form of another verb (e.g., 食べすぎる, 働きすぎる).
昨日のパーティーで飲みすぎて、今日は頭が痛い。
I drank too much at yesterday's party and have a headache today.
彼はいつも仕事をしすぎるから、体を壊さないか心配だ。
He always overworks, so I'm worried he might ruin his health.