Where does “mem” come from?

mem (Ido) comes from French même, from Middle French mesme, from Old French mesme, from Old French meïsme, from Vulgar Latin metipsimus, from Latin ipse, from Proto-Italic *e(s)peso — himself, herself, itself.

mem (Ido): even, still; really, indeed

Definitions

even, still; really, indeed

Ancestry of “mem”, step by step

Step	Language	Word	Meaning
1	French	même	even; same; very
2	Middle French	mesme	same; even
3	Old French	mesme	same; used for emphasis
4	Old French	meïsme	Alternative form of mesme
5	Vulgar Latin	metipsimus	same
6	Latin	ipse	himself, herself, itself, the very, the actual;...
7	Proto-Italic	*e(s)peso	himself, herself, itself

Every word from Proto-Italic *e(s)peso →Every word from Latin ipse →Every word from Vulgar Latin metipsimus →