The spelling of the word "moest" may seem perplexing at first, but its origin stems from its Dutch equivalent "moesten." In IPA phonetic transcription, it is pronounced as /muːst/. The "oe" combination produces a long "oo" sound, while the "st" ending is a typical way to create past tense in Dutch. Although rare in modern English, this word is occasionally used to refer to the act of "musting," or having a compulsion or obligation to do something.