unmerciful

Mane (Îngilîzî)

not showing mercy

Hevwate

merciless

cruel

ruthless

pitiless

unrelenting

remorseless

relentless

heartless

brutal

unkind

tyrannous

unfeeling

unpitying

unsparing

absolute

vicious

cutthroat

ferocious

fierce

harsh

inclement

inexorable

inhumane

lawless

savage

Werger

impitoyable

spietato

άσπλαχνος

unbarmherzig

impietoso

merhametsiz

despiadado

implacable

impiedoso

insaniyetsiz

implacabile

feroce

crudele

άσπλαγχνος

Wekî (IPA) tê bilêvkirin

/ʌnˈmɝsɪfl̩/

Etîmolojî (Îngilîzî)

Ji Middle English mîras hatiye girtin: unmerciful

In summary

From Middle English unmerciful, unmercifull; equivalent to un- + merciful.