thumb rule
The sexist rule schools follow, forcing female students' shorts to go to at least their thumbs, making it almost impossible to find an acceptable pair of shorts.
Teacher: Miss, your shorts don't follow the thumb rule.
Girl: They're the longest I could find.
Teacher: They're distracting the boys in the class.
Girl: They're the longest I could find.
Teacher: They're distracting the boys in the class.