syllable (noun): a unit of pronunciation that has one vowel sound, and may or may not be surrounded by consonants. A syllable can form a whole word or part of a word. For example, there is one syllable in cat, two syllables in monkey and three syllables in elephant.
To understand word stress, it helps to understand syllables.
Every word is made from syllables.
Each word has one, two, three or more syllables.
|word||number of syllables|
Notice that (with a few rare exceptions) every syllable contains at least one vowel (a, e, i, o or u) or vowel sound.