Open English Wordnet
Adjectives
(a)retentive, recollective, long, tenaciousgood at remembering“a retentive mind”, “tenacious memory”
(s)dogged, dour, persistent, pertinacious, tenacious, unyieldingstubbornly unyielding“dogged persistence”, “dour determination”, “the most vocal and pertinacious of all the critics”, “a mind not gifted to discover truth but tenacious to hold it” (T.S.Eliot), “men tenacious of opinion”