at the mercy of

Idioms  

1. Also, at someone's mercy . Subject to the power of, helpless against, as in The captured rebels were at the mercy of the army commander . [Late 1500s]

2. Without any protection against, as in On top of Mount Washington we were at the mercy of the elements . [Late 1600s]

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Example Sentences

Olly, who is the fifth generation of his family to farm on the site, said after the closure of a fertiliser factory in nearby Wirral about three years ago he had become "completely at the mercy of imported fertiliser just to grow crops".

From BBC

"Insects are cold-blooded, so they are at the mercy of external temperatures," said Northwestern's Marco Gallio, who led the study.

From Science Daily

Confidence in the near-term prospects may be brittle—and at the mercy of developments in the Middle East —but several bullish signs have emerged that should give rise to longer-term optimism.

From Barron's

The main risk is that by locking your money away in exchange for a monthly income at a predetermined interest rate, you are at the mercy of a massive surge in inflation and interest rates.

From MarketWatch

Stocks were falling Friday as Wall Street remained at the mercy of the Iran war and ever-changing oil prices.

From Barron's