(noun) Senior Grass is a random patch of grass located in the middle of school courtyards that only Seniors and Teachers can walk on. It is often only in private of magnet schools such as Davidson Fine Arts, in which Seniors aren't allowed to do Senior-y things like leave school an hour early, and therefore require some compensation.
Senior Grass often brings out bad cases of Senioritis, which can cause but is no limited to: Seniors skipping class and sitting on the grass, Seniors playing Ultimate Frisbee, and Seniors starting random games in which Juniors, Underclassmen, and Middle Schoolers are not allowed to participate in.
Senior Grass also causes Seniors to be come violently possessive. They often times yell, scream, and wave their arms/shake fists at Juniors and Underclassmen (i.e. 10th, 9th, 8th, 7th, or 6th graders) who step onto their grass. They can become but rarely are violent enough to tackle an Underclassmen or Junior, but rarely are said children injured enough to go to the hospital.
Note: Senior grass may belongto 8th graders under the rare chance that all highschoolers are missing.
Lilly: Man those Senior's have Senioritis
Marianna: yeah, they got so possessive of that Senior Grass that they even tried to punch that kid!
Emma: Stay of the Senior Grass!
Lilly: You aren't a Senior.
Emma: Yeah, but there aren't any Highschoolers, so I'm a Senior today!