(あとだ)

あとだし
noun
showing one's hand late; acting after seeing others' moves
leisure
1. showing one's hand late (esp. cheating at janken); acting only after others
Deliberately making one's move after seeing what an opponent has done, so as to gain an unfair advantage. Originally the cheating move in janken; widely used figuratively for opinions or decisions made only once the outcome is clear.
後出(あとだ)ずるい。
Showing your hand late is unfair.
じゃんけん後出(あとだ)していけない。
You must not throw late in rock-paper-scissors.
Complaining only after the results are out is like showing your hand late.

"(あと)" (after) + "()し" (putting out). Literally throwing one's janken hand after the opponent. Takes する: 後出(あとだ)する.

Common collocations

  • 後出(あとだ)じゃんけん: cheating at janken by throwing late (also a common metaphor for hindsight criticism)
  • 後出(あとだ)する: to show one's hand late
  • 後出(あとだ)批判(ひはん)する: to criticize with the benefit of hindsight

Usage

Carries a strong negative nuance of unfairness. The figurative 後出(あとだ)じゃんけん is often aimed at people who state an opinion only once the safe answer is obvious.