Synonyms of merciless

merciless

adjective

ˈmər-si-ləs 

as in ruthless

having or showing a lack of sympathy or tender feelings

she is a merciless competitor at board games of any kind

Synonyms & Similar Words

• ruthless
• stony
• pitiless
• brutal
• hard
• oppressive
• harsh
• unmerciful
• cruel
• abusive
• remorseless
• heartless
• stern
• callous
• vicious
• inhuman
• compassionless
• malicious
• unsparing
• hateful
• tough
• grim
• inhumane
• soulless
• unfeeling
• obdurate
• insensitive
• take-no-prisoners
• hard-hearted
• unsympathetic
• uncharitable
• cold-blooded
• insensate
• thick-skinned
• slash-and-burn
• severe
• indurate
• savage
• affectless
• pachydermatous
• desensitized
• hard-boiled
• case-hardened
• thoughtless
• uncaring
• rough
• ironhearted
• heedless
• unthinking
• mean
• stonyhearted
• ungentle
• unfriendly
• boorish
• inconsiderate
• spiteful
• malevolent
• unloving
• virulent
• cold
• disagreeable
• rough-and-tumble
• heavy-handed
• brutish
• barbarous
• surly
• ironfisted
• acrimonious
• bestial
• jackbooted
• sledgehammer
• rancorous
• ill-natured
• ironhanded
• hard-bitten
• evil-minded
• ill-tempered
• austere
• frosty
• knock-down, drag-out

Antonyms & Near Antonyms

• sympathetic
• warm
• sensitive
• merciful
• gentle
• humane
• compassionate
• charitable
• benevolent
• kind
• kindly
• mild
• tender
• lenient
• friendly
• kindhearted
• indulgent
• gracious
• softhearted
• warmhearted
• tenderhearted
• cordial
• benignant
• loving
• tolerant
• affectionate
• good-natured
• understanding
• clement
• fond
• good-tempered

Example Sentences

Recent Examples of merciless

With a merciless 56-22 thumping of Oregon in the Peach Bowl, the Hoosiers punched their ticket to their first national championship game appearance in program history. —Jackson Thompson, FOXNews.com, 10 Jan. 2026

All the while, the president, his top advisers, and his public-affairs offices have pumped out rhetoric and imagery that celebrates the merciless, military-style pursuit of deportations. —Caitlin Dickerson, The Atlantic, 9 Jan. 2026

The Knicks faithful can be merciless like that sometimes. —Kristian Winfield, New York Daily News, 3 Jan. 2026

With no escape, the young band members (played by Anton Yelchin, Alia Shawkat, Joe Cole, and Callum Turner) are forced into a vicious fight for survival against merciless extremists, led by Patrick Stewart's sinister Darcy Banker. —Allison Degrushe, Entertainment Weekly, 31 Dec. 2025