Question: When I type any word ending with an 'l' (ell, like "local") and then press the `/` key, the 'l' is replaced with another symbol and the slash, '/', is omitted. How can I deactivate that function?

[![enter image description here](https://i.stack.imgur.com/lBxkj.gif)](https://i.stack.imgur.com/lBxkj.gif)

Answer: 
Seeing that you use white on black, I take it you use the "Pro" profile (unless you duplicated it or created a fresh new one).

I would look into Terminal's preferences and check the used encoding and other options. If there are differences with, let's say the "Basic" profile, try to see if using that profile is behaving the same or behaves as you would expect. If it is as you expect it, see about changing your used profile more and more to the comparison.
This looks to me like a rendering bug rather than a feature. I would try increasing the font size on your terminal.