Pitch accent is a feature of certain languages whereby variations in pitch (linguistic tones) can be used to differentiate words, but where the potentially distinctive tones are restricted to only one or two syllables within a word – as opposed to fully tonal languages like Standard Chinese, where each syllable can have an independent tone. In a pitch accent language, the syllable with phonemic tone is typically one that is acoustically prominent (stressed). Also many words may not be marked for tone at all.