mer·cy 
/ˈmɚsi/ noun
plural mer·cies /ˈmɚsi/ noun 1 [noncount] : kind or forgiving treatment of someone who could be treated harshly
▪ He is a vicious criminal who deserves no mercy. ▪ She fell to her knees and asked/begged/pleaded for mercy. ▪ Have you no mercy? = Are you utterly without mercy? ▪ May God have mercy on us all. [=may God treat us all with kindness and forgiveness] ▪ He showed no mercy to his enemies. = He showed his enemies no mercy. [=he treated his enemies very harshly] ▪ The boss took mercy on us [=he treated us kindly] and let us go home early. ▪ a man of mercy [=a man who treats other people with kindness and forgiveness] ▪ The prisoner confessed his crimes and threw himself on the mercy of the court. [=the prisoner begged the court for mercy] 2 [noncount] : kindness or help given to people who are in a very bad or desperate situation
▪ an act of mercy ▪ They came on a mission/errand of mercy to provide food and medical care for starving children. ▪ a mercy mission 3 [count] : a good or lucky fact or situation
▪ It's a mercy that the building was empty when the fire started. ▪ We should be grateful/thankful for small mercies. [=even though bad things have happened to us, we should be grateful that our situation is not worse] ▪ Thank heaven for small mercies. 4 old-fashioned + informal — used as an interjection to show surprise ▪ Mercy! That wind is cold! ▪ I'm not hungry, but mercy [=heavens, goodness], that food sure does smell good! ▪ Mercy me! That wind is cold.
▪ He is a vicious criminal who deserves no mercy. ▪ She fell to her knees and asked/begged/pleaded for mercy. ▪ Have you no mercy? = Are you utterly without mercy? ▪ May God have mercy on us all. [=may God treat us all with kindness and forgiveness] ▪ He showed no mercy to his enemies. = He showed his enemies no mercy. [=he treated his enemies very harshly] ▪ The boss took mercy on us [=he treated us kindly] and let us go home early. ▪ a man of mercy [=a man who treats other people with kindness and forgiveness] ▪ The prisoner confessed his crimes and threw himself on the mercy of the court. [=the prisoner begged the court for mercy]
▪ an act of mercy ▪ They came on a mission/errand of mercy to provide food and medical care for starving children. ▪ a mercy mission
▪ It's a mercy that the building was empty when the fire started. ▪ We should be grateful/thankful for small mercies. [=even though bad things have happened to us, we should be grateful that our situation is not worse] ▪ Thank heaven for small mercies.
at the mercy of or at someone's or something's mercy
: in a position or situation in which you can be harmed by (someone or something you cannot control)
▪ With no way to control the ship, we were at the mercy of the sea. ▪ The people were at the mercy of the advancing army. = The army advanced, and the people were at their mercy. [=the people could do nothing to defend themselves from the army] ▪ Our plans were at the mercy of the weather.
▪ With no way to control the ship, we were at the mercy of the sea. ▪ The people were at the mercy of the advancing army. = The army advanced, and the people were at their mercy. [=the people could do nothing to defend themselves from the army] ▪ Our plans were at the mercy of the weather.
to the mercy of or to the (tender) mercies of
: without any protection from (someone or something you cannot control)
▪ He had to leave his boat to the mercy of the storm. ▪ As the army retreated, the people were left to the mercies of the advancing enemy.
▪ He had to leave his boat to the mercy of the storm. ▪ As the army retreated, the people were left to the mercies of the advancing enemy.
