Learn how to say Mercy correctly in English with this tutorial pronunciation video.
Oxford dictionary definition of the word mercy:
compassionate treatment of or attitude towards an offender, adversary, etc, who is in one’s power or care; clemency; pity
the power to show mercy ⇒ to throw oneself on someone’s mercy
a relieving or welcome occurrence or state of affairs ⇒ his death was a mercy after weeks of pain
See at the mercy of
C12: from Old French, from Latin mercēs wages, recompense, price, from merx goods