As adjectives the difference between tenacious and relentless
is that tenacious is clinging to an object or surface; adhesive while relentless is unrelenting or unyielding in severity.
tenacious
English
Adjective
(
en adjective)
clinging to an object or surface; adhesive
unwilling to yield or give up; dogged
holding together; cohesive
having a good memory; retentive
Synonyms
* See also
relentless
English
Adjective
(
en adjective)
Unrelenting or unyielding in severity
Unremitting, steady and persistent
Derived terms
* relentlessness