Latin word that Euler used for "illustrative example" I'm getting old and forgetful.
Everyone here knows the difference between theorem, corollary, lemma, proposition, conjecture, axiom, and postulate.
I once heard another one, a Latin term, that IIRC meant something like "illustrative example." The only example I ever found of it being used was from Euler.
It may be rare, but I like having a complete list. Can someone help me out and remind me what this mathematical term is?

Here is one, which I like:
scholium NOUN (pl. scholia)
Pronunciation /ˈskəʊlɪəm/
historical
A marginal note or explanatory comment made by a scholiast.
‘They fall into two categories: the first, a group of ten plays which have been transmitted to us in our medieval manuscripts complete with the accumulation of ancient notes and comments that we call scholia.’
Origin
Mid 16th century modern Latin, from Greek skholion, from skholē ‘learned discussion’.
Lexico
