Performed to an extent not enjoined or not required by duty.
A teacher in high school had a grading system that we, at the time, thought was unique. It was not unique but it seems to have been unusual as I’ve never met anyone who encountered this grading technique in their school years.
Instead of the clumsy sounding "supererogatory" (which has a strangely sexual sound to it) our teacher handed out the coveted "ABCD." "ABCD" stands for "Above and Beyond the Call of Duty" and was a grade that rose above A+. This teacher used this grade sparingly, as I recall, though I seem to remember landing an ABCD quite a few times.
One could not, unfortunately, get an "ABCD" grade on a final report card, though it might have been entertaining to explain such a grade to college admissions boards.
I was somewhat ambivalent about this grade. Despite what it stood for I felt that those 4 letters in a row suggested that my work comprised all grades from A to D, and was thus uneven or mediocre: "A careless mix of insight and carelessness," as a college professor once memorably wrote on an essay of mine. Somehow a grade ending in a D didn’t sound so great to me.
