Nouns

(n)testimony, testimonialsomething that serves as evidence“his effort was testimony to his devotion”
(n)tribute, testimonialsomething given or done as an expression of esteem
(n)recommendation, testimonial, good wordsomething that recommends (or expresses commendation of) a person or thing as worthy or desirable

Adjectives

(a)testimonialexpressing admiration or appreciation“testimonial dinner”
(a)testimonialof or relating to or constituting testimony