Pitiless is a related term of fiendish.
As adjectives the difference between pitiless and fiendish
is that pitiless is having, or showing, no pity; merciless while fiendish is sinister; evil; conniving; in the manner of a fiend.
pitiless
English
Adjective
(
en adjective)
having, or showing, no pity; merciless
having no kindly feelings; unkind
Derived terms
* pitilessly
Anagrams
*
fiendish
English
Adjective
(
en adjective)
Sinister; evil; conniving; in the manner of a fiend.
Derived terms
* fiendishly
* fiendishness
Anagrams
* finished