noun
overdoing; going too far; overkill
Refers to excessive action, effort, or behavior; often used critically when someone has gone beyond reasonable limits.
彼の冗談はいつもやり過ぎだ。
His jokes are always over the top.
ダイエットのやり過ぎで体調を崩した。
I got sick from overdoing my diet.
過剰 is a more formal noun meaning 'excess' or 'surplus', often used in technical or quantitative contexts, while やり過ぎ is a colloquial noun for 'overdoing' in actions or behavior.
行き過ぎ also means 'going too far' but often implies physically passing a point or an extreme in opinion/action; やり過ぎ focuses on excessive doing or effort.
Compound of the verb stem やり (from やる 'to do') and 過ぎ (from すぎる 'to exceed'). Literally 'doing too much'.