The word "Haoa" is a challenging one to spell due to its unique pronunciation. It is pronounced as /haʊ.a/ which means that it is a two-syllable word with an "ow" sound and ends with an "a" sound. The "h" sound at the beginning is pronounced with aspiration, which means that it is accompanied by a puff of air. The vowel "a" is pronounced as a diphthong, which means that it is a combination of two vowel sounds "ah" and "oh". Therefore, the correct spelling of "Haoa" is crucial to ensure that it is pronounced correctly.