Hol”la, interj. [F. hola; ho ho + l[`a] there, fr. L. illac that way, there. Cf. Hollo.] Hollo.
-source: dictionary.com
holla
1. a word used to acknowledge the presence of a fellow companion
Is that mah boy ova there? HOLLAAAAA!
2. For a man to express interest in a particularly impressive female specimen
Watch out, I’m about to holla at this fine bitch.
source: urbandictionary.com