1. a solid agreement on something truly amazing
2. used to voice one's approval or excitement of something
Person 1: We're gonna beast those dance moves tomorrow night!
Person 2: Holla hard!
Person 1: We're awesome!
Person 2: Oh, yeah! Holla hard!
Guy 1: Dude, did you hear?? The new Pokemon video game is out!! This is frikkin awesome!!
Guy 2: ...oh holla HARD!