Simple Definition of merciless
: having or showing no mercy : very cruel or harsh
Examples of merciless
the merciless killing of innocent people
He has been merciless in his criticism of his opponent.
First Known Use of merciless
MERCILESS Defined for Kids
Definition of merciless
: having no mercy or pity <These people, she thought, would be merciless critics. — Lucy Maud Montgomery, Anne of Green Gables>
Seen and Heard
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