A weeder class is a class (typically in college) that is characterized by having a large dropout rate due to rigorous expectations, such as hard tests, impossible studying requirements (15 hours a week or more), and homework up the ASS. These classes "weed" out those who lack the motivation to keep going or simply cannot take it up the ass anymore. Only the (really) hard-working, gifted, and borderline insane students make it through weeder classes. Note: Weeder classes can seriously traumatize an individual, destroy any ounce of confidence they have, and make them seriously reconsider majors as most weeder classes are required.
At the beginning of the quarter the Intro to Mechanical Engineering class had 70 students. By the end of quarter, only 30 remained. That class is a weeder class. If you plan on taking this class, PREPARE YOUR ANUS.

Some infamous weeder classes: All calculus classes, physics, chemistry, and engineering intro classes.
by Cochiloco April 7, 2014
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