If your TikTok feed is currently filled with videos of college girls showing off their “OOTD” (Outfit of the Day) during rush week, you’re witnessing one of the most anticipated traditions in American college life. Known as rush week, this period marks the beginning of recruitment season for sororities and fraternities across campuses nationwide.

Rush week is a multi-day event where students hoping to join a Greek organization go through a series of activities. These include visiting fraternity or sorority houses, having one-on-one conversations with current members, and showcasing why they’d be a good fit. The ultimate goal is to receive an invitation — known as a “bid” — to become part of a particular group.

For many outsiders, Greek life can feel confusing due to its unique culture and terminology. If you’re new to this, here’s a guide to some of the most commonly used words during rush week and within Greek organizations.

Active
An active is a student who has already been officially initiated into a fraternity or sorority and currently participates in its activities.

Bid
A bid is the formal offer extended to a potential new member, inviting them to join a sorority or fraternity. It usually comes at the end of rush week, after rounds of interviews and social events.

Bid Day
This is the day when new members find out which house they’ve been accepted into. It’s a big celebration — houses are decorated, chants are shouted, and new members are welcomed with open arms.

Big/Little
Once accepted, a new member — known as a “little” — is paired with a mentor from within the organization. This mentor, known as a “big,” is typically an older member who provides support, guidance, and friendship.

Brother/Sister
In the world of Greek life, members refer to one another as brothers or sisters, depending on whether it’s a fraternity or sorority. This emphasizes the strong bond and family-like atmosphere within the organization.

Chapter
Each Greek organization has chapters at different colleges and universities. These local chapters operate under a larger national body, but they host their own meetings, events, and rituals.

Dues
Joining a sorority or fraternity comes with financial responsibilities. Members are required to pay dues — regular fees that help cover social events, operational costs, and other activities.

Fraternity/Sorority
These are the official names for Greek-letter organizations. Fraternities are generally for men, while sororities are for women. These groups are known for their strong social networks, lifelong memberships, and involvement in charity and campus events.

Greek Life
The umbrella term for everything related to fraternities and sororities at a college is known as Greek life. This includes recruitment, social functions, philanthropy efforts, leadership development, and more.

While rush week may look like a fashion show on social media, it’s much more than that. For many students, it’s a doorway to friendships, personal growth, leadership opportunities, and a lifelong connection to a community. Understanding the culture and terms used in Greek life is the first step to making sense of this vibrant college tradition.