Definition of "dux"

[…] on the motion of Sir John Marjoribanks, Bart., Lord Provost, unanimously resolved, July 27, 1814, “that there be annually presented by the town of Edinburgh to the boy at the head of the Greek class, taught by the rector of the High School, a gold medal of the same value [five guineas] as that annually presented to the dux of the Latin class.”

1849, Wilhelm Steven, The History of the High School of Edinburgh, page 191

He finished the year dux of Form III with an average 90 per cent over eight subjects. The school did not award end-of-year marks in fourth and fifth forms, but Evans′ report for those years shows he passed all subjects in both years and was again dux in Form V.

1999, Keith Scott, Gareth Evans, page 29

This school was where my father had been dux in his senior year in 1937 just as his father had been dux at the Rockhampton Grammar School27 before the turn of the 19th century.

2010, Roger K. A. Allen, Ballina Boy, page 28

Quite a few who became national athletic champions were also duxes or top academic pupils at their schools.

2011, A. Lydiard, Running to the Top, page 17