What’s a Nonius?

If you already know what a nonius is, you can probably skip this post. But, if like us, you would have to look it up, we’ll tell you what we …. It turns out, a translation mistake taught us a new word and some history we weren’t aware of.

In the manual, this is captioned: Figure 4-7 Nonius Display (Standard Mode) Have a look at the adjacent graphic from a waveform display. What would you call the vertical red lines at positions 139 and 200. The manual, however, calls each one a “nonius”.

Oddly, the manual also has sentences like “ Select one nonius and right-click, and then select ‘Remove Marker’ in the next window to delete the nonius.” So, clearly, a nonius is the vertical line marker or cursor. But that, of course, begs a question… What is a Nonius.