A derogatory term used by mentally challenged or very low IQ institutionalized males or females used to put down another mentally challenged person. Sometimes used against their careworkers. Normally used in a retallitory manner and refering to the others IQ. I personally never experienced this term outside of an institutioanlized situation. And found this was this worst verbal insult said person could use. If you are called a low grade you have not been complimented. I like to used the term in the car to prevent road rage as it is safe around children and it really helps as only I (until now) know how bad I've insulted the driver of the other vehicle.
Oh you think I'm a dummy. Well you're a low grade. Low grade, low grade, low grade!

Children you should never drive like that. It is unsafe and that person is a low grade.
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The phenomenon of posting online about a graded collectible whereby the original poster will always apologize for the low quality of said collectible.
"Just bought a new-to-me copy of Avengers #1, sorry for the low grade." Got them Low Grade Blues
by Slimcady March 3, 2023
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