The spelling of the word "unbelieves" may seem confusing, but it's actually quite straightforward when broken down using IPA phonetic transcription. The first syllable is pronounced "uhn," with a short "u" sound like in "cup." The next syllable is "buh," which includes a short "e" sound like in "bet." Finally, the last syllable is "leeves," which includes a long "e" sound like in "tree." When put together, the word is spelled "un-buh-leevz."
The word unbelieves is actually a derivative of the word unbelief. The etymology of unbelief can be traced back to Middle English, specifically from the combination of the prefix un- (meaning not) and the noun belief. Belief, in turn, can be traced back to Old English, where it was derived from the verbs be and lief (meaning to wish or to desire). Over time, belief evolved to refer to the acceptance or conviction of something as true, while unbelief refers to the absence or refusal of such acceptance or conviction. The addition of the suffix -s to unbelief forms the verb unbelieves.