2. Interjection. (slang) (non-gloss definition A greeting similar to hi.) ¹
3. Interjection. (slang) (non-gloss definition An interjection similar to hey.) ¹
4. Interjection. (military slang) Present! Here! ¹
5. Contraction. (African American Vernacular English) contraction of you and are ¹
6. Pronoun. (colloquial) shortened form of your. ¹
7. Pronoun. (context: Baltimore) third-person singular, familiar ¹
¹ Source: wiktionary.com
Definition of Yo
1. used to call attention or to express affirmation [interj]