Presumingly is a word that means "assumed or believed to be true without proof or confirmation." There are several synonyms for presumingly, including seemingly, apparently, purportedly, allegedly, and supposedly. Seemingly and apparently suggest that something appears to be true based on what is observed or known. Purportedly and allegedly imply that something is claimed to be true, but there may be doubts about its veracity or evidence to back it up. Supposedly suggests that something is assumed to be true, but again, there may be uncertainty or a lack of confirmation. All of these words convey the idea of something being assumed to be true, but with varying degrees of confidence or skepticism.