The spelling of the word "bourgoin" can be explained with the use of IPA phonetic transcription. In IPA, the word is pronounced as /bʊrˈɡwɑ̃/, which corresponds to its French origin. The "oi" combination in the word is pronounced as /wã/, which is similar to the nasal vowel sound in the English word "song". The "g" and "n" sounds combine to create the nasal consonant sound represented by /ɲ/, which is similar to the "gn" sound in the French word "champagne".