testimonialEnglishOxford English Thesaurustestimonial noun 1 Sir Hans drafted a glowing testimonial for him: reference, character reference, recommendation, letter of recommendation, commendation, endorsement, certificate of competence; dated character. 2 in 1848 Airy received a testimonial from the Royal Astronomical Society: tribute, presentation, gift, trophy; memento, souvenir.testimonial Oxford Dictionary of English