Warren Cole had originally assigned Zeta designations (or chapter names) in the order of anticipated petitions rather than when chapters were officially chartered and established.
His original intention was to designate Zetas by the standard Greek alphabet. In April of 1913 (with seven chapters already designated), Jack Mason developed a post-hoc rationale for the haphazard order, sentences that collectively order the twenty-four Greek letters:
A Good Energetic Zeta Is Lambda’s Boast- Strength From Delta Pi – Our Motto, To Each Through Union; Excellent Character Only, Knowing No Retreating Steps.
The Zeta Song
When the 25th Zeta was established, the same sequence was stipulated for the prefix or “series.” (i.e. Alpha-Alpha)
When Lambda Chi Alpha merged with Theta Kappa Nu in 1939, each former Theta Kappa Nu chapter were given a Zeta designation beginning with Theta, Kappa, or Nu. At the twenty-one (21) schools where Lambda Chi Alpha already had a chapter, these designations were still assigned but never used. A total of 55 Theta Kappa Nus made for 24 Theta-series, 24 Kappa-series, and 7 Nu-series.
| Single-letter Series | 1909-1915 |
| Alpha Series | 1915-1918 |
| Gamma Series | 1919-1926 |
| Epsilon Series | 1926-1945 |
| Theta, Kappa, & Nu Series | |
| Zeta Series | 1946-1951 |
| Iota Series | 1951-1963 |
| Lambda Series | 1964-1970 |
| Beta Series | 1970-1972 |
| Sigma Series | 1972-1976 |
| Phi Series | 1977-1986 |
| Delta Series | 1987-2003 |
| Pi Series | 2004-2017 |
| Omicron Series | 2018-Present |
