"Marvelment" is a fairly rare word, meaning astonishment or wonder at something remarkable. Synonyms for "marvelment" could include terms like amazement, awe, admiration, fascination, or even stupefaction. Other possible options might include words like surprise, shock, or disbelief, depending on the context. Some people might use phrases like "jaw-dropping" or "mind-blowing" to describe moments of marvelment. Ultimately, the choice of synonym will depend on the situation at hand and the specific nuances of the word needed to capture the speaker's or writer's intended meaning. Regardless of the chosen term, however, all of these words convey a sense of powerful emotion and deep reverence in the face of something truly extraordinary.