Greek Letters in Fraternities and Sororities

Fraternities and sororities — collectively called "Greek life" or "the Greek system" — name themselves with two or three Greek letters, like ΦΒΚ (Phi Beta Kappa) or ΔΓ (Delta Gamma). The tradition began at the College of William & Mary in 1776 and has spread across North American universities ever since. Today there are roughly 750 Greek-letter organizations in the U.S. alone, with combined membership in the millions. This page explains why the letters, what they typically stand for, and what the biggest organizations are.

The Origin: Phi Beta Kappa, 1776

On December 5, 1776 — six months after the Declaration of Independence — five students at the College of William & Mary in Williamsburg, Virginia formed a secret society they called Phi Beta Kappa (ΦΒΚ). The three letters were the initials of their Greek motto: Φιλοσοφία Βίου Κυβερνήτης (Philosophía Bíou Kybernétēs), meaning "Philosophy is the guide of life." Greek was chosen because:

• Greek was the language of higher learning in 18th-century universities — every educated young man studied Greek and Latin.
• The letters concealed the motto. Only members knew what ΦΒΚ stood for; outsiders saw three mysterious symbols.
• Greek lent gravitas. Ancient Greek philosophy and democracy were the moral references of Revolutionary-era America.
• It was distinctive. No other student group used letters that way.

Phi Beta Kappa quickly evolved from a debating society to an academic honor society — recognizing the top students at participating universities — and remains so today. Its decision to go Greek set the template for everyone who came after.

The Spread of the Greek System

For about fifty years after 1776, Phi Beta Kappa was unique. Then, in 1825, Kappa Alpha Society formed at Union College in Schenectady, New York — the first "social" Greek-letter fraternity, modeled on Phi Beta Kappa but focused on brotherhood rather than scholarship. Sigma Phi (1827) and Delta Phi (1827) followed at the same college, forming what's still called the "Union Triad."

From Union, the pattern spread:

• 1825–1850: Founding decades for the oldest social fraternities. Most originated at Union, Hamilton, Yale, and other northeastern colleges.
• 1851: Adelphean Society (now Alpha Delta Pi) founded at Wesleyan Female College in Georgia — the first women's Greek-letter society, predating the term "sorority."
• 1870: Kappa Alpha Theta and Kappa Kappa Gamma founded at DePauw — the first women's organizations to call themselves "fraternities" using Greek letters in the modern style.
• 1874: "Sorority" coined as a feminine alternative to "fraternity," from Latin soror (sister).
• 1906: Alpha Phi Alpha founded at Cornell — the first historically Black Greek-letter intercollegiate fraternity. The "Divine Nine" of historically Black sororities and fraternities formed in the following decades.
• 1898–present: Latino, Asian, Jewish, multicultural, and professional Greek-letter organizations continue to form, each often with culturally specific traditions but using the same Greek-letter convention.

How the Names Work

Almost every Greek-letter organization name follows the same pattern: two or three Greek letters, which are the initials of a Greek motto kept secret to members. The motto typically expresses the organization's founding values — virtues like wisdom, friendship, service, or justice. Letters are pronounced individually ("Phi Beta Kappa"), not as if they spelled a word.

• Most common: Three letters (e.g., Sigma Alpha Epsilon, Alpha Delta Pi).
• Two letters: Less common but historically older (e.g., Phi Delta — actually Phi Delta Theta — drops the third in casual reference; Kappa Alpha — abbreviated KA).
• Four letters: Rare; sometimes used for honor societies or more recent organizations (Sigma Theta Tau, the nursing honor society).
• Secret mottos: The actual Greek phrase is usually known only to initiated members. Phi Beta Kappa is an exception — its motto is public.

Major North American Fraternities (Selected)

Major North American Sororities (Selected)

The "Divine Nine"

The National Pan-Hellenic Council (NPHC), informally called the "Divine Nine," is the umbrella group for the nine historically Black Greek-letter organizations, all founded in the early 20th century when most existing fraternities and sororities barred Black members. The nine are:

• Alpha Phi Alpha (ΑΦΑ) — 1906, Cornell
• Alpha Kappa Alpha (ΑΚΑ) — 1908, Howard
• Kappa Alpha Psi (ΚΑΨ) — 1911, Indiana
• Omega Psi Phi (ΩΨΦ) — 1911, Howard
• Delta Sigma Theta (ΔΣΘ) — 1913, Howard
• Phi Beta Sigma (ΦΒΣ) — 1914, Howard
• Zeta Phi Beta (ΖΦΒ) — 1920, Howard
• Sigma Gamma Rho (ΣΓΡ) — 1922, Butler
• Iota Phi Theta (ΙΦΘ) — 1963, Morgan State

Honor Societies and Professional Fraternities

Beyond social fraternities and sororities, hundreds of Greek-letter organizations exist for specific academic disciplines or professions. A few of the largest:

• Phi Beta Kappa (ΦΒΚ): Liberal arts honor society, the oldest.
• Tau Beta Pi (ΤΒΠ): Engineering honor society.
• Phi Kappa Phi (ΦΚΦ): All-discipline honor society.
• Sigma Xi (ΣΞ): Scientific research honor society.
• Alpha Lambda Delta (ΑΛΔ): Freshman academic honor.
• Beta Alpha Psi (ΒΑΨ): Accounting, finance, IS honor.
• Sigma Theta Tau (ΣΘΤ): Nursing honor.
• Delta Sigma Pi (ΔΣΠ): Co-ed professional business fraternity.
• Phi Mu Alpha (ΦΜΑ) Sinfonia: Music fraternity for men.
• Alpha Phi Omega (ΑΦΩ): Co-ed service fraternity.

Common Letters in Organization Names

Some Greek letters appear far more often in fraternity and sorority names than others. The most common are:

• Alpha (Α): Suggests being first or foundational. Appears in many names: Alpha Phi Alpha, Alpha Kappa Alpha, Alpha Tau Omega, Alpha Sigma Phi, Alpha Chi Omega, etc.
• Beta (Β): Often paired with Phi or Sigma. Beta Theta Pi, Phi Beta Kappa, Phi Beta Sigma.
• Delta (Δ): One of the most frequent. Delta Tau Delta, Delta Gamma, Delta Sigma Theta, Alpha Delta Pi, Delta Delta Delta.
• Sigma (Σ): Extremely common; usually associated with brotherhood/sisterhood. Sigma Chi, Sigma Nu, Sigma Phi Epsilon, Sigma Alpha Epsilon, Sigma Gamma Rho.
• Phi (Φ): The "Phi" in many group names typically comes from φιλία (philía, "friendship"). Phi Mu, Phi Beta Kappa, Phi Delta Theta.
• Omega (Ω): Suggests culmination or completion. Omega Psi Phi, Chi Omega, Alpha Phi Omega.

Less common: Xi, Theta (less frequent than expected), and obscure-to-many letters like Zeta and Eta, though they do appear (Zeta Tau Alpha, Eta Sigma Phi).

Practical Notes

• Writing Greek letters: Members typically write Phi Beta Kappa as both "ΦΒΚ" (Greek characters) and "PBK" (Latin transliteration) depending on context. See our keyboard guide for how to type Greek letters.
• Pronouncing names: Each Greek letter is pronounced separately — never as if the letters formed a word. See our pronunciation guide.
• Color-coding and crests: Each organization has signature colors, a crest, a flower, and a jewel. These are unrelated to the letters themselves.
• Variants: "Theta" appears in names where it's often shortened in speech (Kappa Alpha Theta = "Theta," Delta Sigma Theta = "Delta"). The shortcut varies by organization.

Related Pages

• Greek alphabet in culture — broader cultural uses including Greek life.
• Full Greek alphabet reference — names, pronunciations, meanings of each letter.
• Phi, Beta, Sigma, Delta — the most common Greek-life letters.