I remember this topic being discussed in the AGD forum, and greeklawgirl cracked the code! This is how AGD names our chapters:

There were five original provinces, and they were named as follows:

Alpha: NorthEast
Beta: Upper Midwest
Gamma: Southeast
Delta: West
Epsilon: Lower Midwest

Alpha went through the entire alphabet with Alpha Omega chartering in 1971. The Northeast chapters then jumped to Zeta, which is the 6th letter of the alphabet.

They're named in groups of five.. so, in keeping with the pattern, this is how future chapters will be named:

The Northeast Province went from Alpha to Zeta. Once we charter Zeta Omega, the northeast chapters will go to Lambda. When they charter Lambda Omega, NE will go to Pi. From Pi it will go to Phi.

Upper Midwest Provence is still on Beta Tau. Once we charter Beta Omega the Upper Midwest will go to Eta, then Mu, then Rho, then Chi.

The Southeast Province went through Gamma, then it jumped to Theta. Once Theta Omega is chartered, SE chapters will jump to Nu, then Sigma, then Psi.

West Province has only gone to Delta Sigma (which happens to be my chapter!), but once it charters Delta Omega, Western Chapters will go to Iota, then Xi, then Tau, then Omega.

Lower MidWest Province finished Epsilon, then moved to Kappa. After Kappa is finished, it would go to Omicron, and then Upsilon.


***I think Maria deserves another round of applause!***