Definition & Meaning of "yo"in English

What does "yo" mean in slang?

"Yo" is a casual greeting used to get someone's attention or start a conversation, similar to "hey" or "hi." The structure is a short, one-syllable interjection with no grammatical complexity, making it quick and informal. It has been widely used in English-speaking street and youth slang for decades and is common in texting, rap music, and casual speech.