In linguistics, the phoneme (unit of spoken sound) sandwiched between one vowel and the following vowel can "belong" to either the preceding syllable, as its coda, or to the following syllable, as its onset. In "dessert," the /z/ sound between the two letters 'e' belongs to the second syllable, as its onset. The same is true of the /d/ in "adore." In "silly," the /l/ sound belongs to the first syllable, as its coda. So does the /n/ in "dinner."
In some words, there is no clear place for the syllable break to occur, and the intervening consonant can belong to either the first syllable or the following syllable. These phonemes are ambisyllabic. Examples include the /m/ in "hammer" and the letter 't' in "water."
Iron Noder 2017, 9/30