The word "more unmemorable" refers to something that is even more forgettable than before. It denotes a lack of distinction or uniqueness that fails to leave a lasting impression. Its antonyms would be words that describe the opposite experience, such as "memorable," "memorial," or "noteworthy." These antonyms express the notion that a given experience, place, or object is distinguished, remarkable, or even unforgettable. The antonyms for "more unmemorable" convey an experience that is worth remembering or a thing of special importance, making it stand out from the mundane or ordinary.