The name "Latus Rectum" sounds so very specific.
Infact when I once asked why it is called as such, an explanation stated that the concave side of a parabola is called a rectum and that latus was just gibberish for a line segment.
Is there a latus somewhere else in geometry other than the latus rectum or did someone just shove that name in for laughs? No, seriously, high schoolers seem to always remember it even if they don't know what a parabola is.
The rect- in rectum is related with the English right or (st)raight, as well as the neologism correct. And latus means side, but also wide, or width. The expression simply means straight side. Which is also why it's probably left untranslated, since (at least word-wise) it's synonymous with the notion of straight line, which however bears different connotations. (In Romanian, for instance, lat means broad, and latura means side, while drept means straight or direct).