一錘定音 [－锤－－]

Jyutping jat1 ceoi4 ding6 jam1
Pinyin yī chuí dìng yīn

Definitions (CC-CEDICT)
  1. lit. to fix the tone with a single hammer blow
  2. fig. to make the final decision
Definitions (粵典–words.hk)
  1. 動詞
    比喻​作出​最終​決定
    to make the final decision; literally: to fix the tone with a single hammer blow
Definitions (Wiktionary)
  1. phrase, idiomatic
    to give the final word
Definitions (Kaifangcidian)
  1. （沒有對應漢語詞彙）