Nickname for Marg Helgenberger of CSI. Given to her by Gary Dourdan at the time of Fergie's "Fergalicious" came out. Marg's fans have come to use the nickname to describe anything pertaining to Marg (or otherwise) as lovely, sexy, sweet, gorgeous, smart, funny, witty, sassy, adorable, eye candy, perfect, etc.
a stunning woman called Megan who has the looks best compared to Jennifer Anniston and the heart best compared to a pot of gold. A woman not only beautiful on the outside but on the inside too. Someone who knows what she wants in life and how to get it and strives for success. Someone who is megalicious also enjoys playing bowls and has stinky feet.