Your Greek roots go back further than those old letter T-shirts your grandbig gave you. Since Greek life was established at GW more than 150 years ago, sororities and fraternities have become a part of University history, now making up a third of our campus population.
Source: wiktionary
Every Little is assigned a Big to mentor them, and it's the Big's job to show them how things are done. Every Big has a Grandbig who is over the Big, and then there's the Great Grandbig, the—"
"Let me guess," I said. "The Mac Daddy of them all."
"I prefer Mac Mother, but yes, you get the idea."
Source: wiktionary