MEANING: noun: A task given, especially as a punishment.

ETYMOLOGY: In the beginning, a pensum was the amount of wool to be spun. Eventually, the word became generic and came to refer to a piece of work or task. Later, it morphed into another specialized form: a task given as a school punishment. The word is from pendere (to hang, weigh), ultimately from the Indo-European root (s)pen- (to draw, to stretch, to spin), which also gave us pendulum, spider, pound, pansy, pendant, ponder, appendix, penthouse, depend, spontaneous, vilipend, filipendulous, perpend, equipoise, pendulous, and pensive. Earliest documented use: 1667.

PERSUM - how you pay an accountant on piecework

OPENSUM - a sub-total

WENSUM - and you lose some