What is a Syllable Counter? A syllable counter is a tool used to determine the number of syllables in a word or phrase. Syllables are individual units of sound in a word, typically containing a vowel sound. Knowing the syllable count of a word is important in the English language as it helps with pronunciation, phonetics, and even poetry.Definition of a Syllable CounterA syllable counter can be a digital tool or a physical method used to count syllables in words.