手てのひらを返かえす

expression, godan verb (-su)

flip-flop; do an about-face; change attitude suddenly

Idiomatic expression describing a sudden, complete reversal of opinion, attitude, or behavior, often with a negative connotation of inconsistency or opportunism. Literally 'to flip over one's palm'.

• 彼かれは昨日きのうまで賛さん成せいだったのに、今日きょうは手てのひらを返かえしたように反はん対たいした。

  He was in favor until yesterday, but today he opposed it as if he had completely changed his mind.

• 上じょう司しは都つ合ごうが悪わるくなるとすぐに手てのひらを返かえす。

  My boss flip-flops as soon as things become inconvenient for him.

expression, godan verb (-su)

do something easy; do with ease

Rare idiomatic use meaning to accomplish something effortlessly, as easily as turning over one's hand. Not commonly used in modern Japanese; the primary sense is the about-face meaning.

• 彼かれは難むずかしい問もん題だいを手てのひらを返かえすように解といた。

  He solved the difficult problem as easily as turning over his hand.