Stress accent refers to the emphasis placed on certain syllables within words, which can affect their pronunciation and meaning. In languages like English, a stressed syllable is typically louder, longer, and pronounced with a higher pitch compared to unstressed syllables. This feature helps distinguish between words and can change the meaning of phrases. Different languages have varying rules for stress accent. For instance, in Spanish, stress often falls on the second-to-last syllable, but exceptions exist. Understanding stress accent is crucial for effective communication, as misplacing stress can lead to misunderstandings or confusion in conversation.