To acknowledge someone. To make ones presence known.

To acknowledge with respect.

1. A message to friends, family, etc. lodged on a radio station, web site, or other popular medium.
2. An inane activity chowing up airwaves, electricity, and bandwidth.

Hint: UrbanDictionary.com is for definitions, NOT SHOUT OUTS.

Like when rapper's thank people when they make a CD. They shout out to god, their family and their crew.

To pass respect to/mention of a relative/girlfriend/boyfriend/ethnic group//city/country/state/college/planet and increasingly being employed by Linux/Unix geeks on a radio station/television station ESPECIALLY that god-awful show Total Request Live. If justice was true to its name, then Carson Daley and crew would be ass-rammed, without lube, by a gaggle of Hispanic prison-inmates who have clicked on penis enlargement emails and have applied for credit cards. In addition to that, the people that appear on the show will receive anal fisting's, again without lube, and then, summarily executed. Amen.