Not every syllable in a word receives equal weight. Stress is the relative emphasis placed on a syllable, realized through loudness, duration, pitch, or a combination, and used to structure words and phrases.

Lexical stress can distinguish meanings in some languages; in others stress position is largely predictable. English uses stress both within words and to highlight new information in sentences. Misplaced stress reduces intelligibility for learners.

Phonologists model stress with feet and prominence hierarchies. Teaching materials mark stressed syllables to support pronunciation. Rhythm types relate partly to how languages deploy stress.

• Prominence of a syllable within a word or phrase
• Cued by loudness, length, and pitch
• May be distinctive or largely predictable
• Affects rhythm and intelligibility