unrelenting vs unappeasable

unrelenting and unappeasable both are adjectives.

Word	Noun	Adjective	Verb	Adverb
unrelenting	No	Yes	No	No
unappeasable	No	Yes	No	No

As adjectives, unrelenting and unappeasable are synonyms defined as:

unrelenting and unappeasable: not to be placated or appeased or moved by entreaty

Other synonyms of unrelenting include grim, inexorable, relentless, stern, unforgiving.

unrelenting (adjective)	unappeasable (adjective)
never-ceasing	not to be placated or appeased or moved by entreaty
not to be placated or appeased or moved by entreaty
punishingly harsh