Where does “intimus” come from?

intimus (Latin) comes from Latin intus, from Latin în, from Latin en, from Proto-Italic en, from Proto-Indo-European h₁én — in.

intimus (Latin): inmost; profound; most or very secret or intimate

Definitions

Step	Language	Word	Meaning
1	Latin	intus	within, inside; at home
2	Latin	în	in, at, on, upon, from (space)
3	Latin	en	lookǃ beholdǃ; reallyǃ?; come onǃ
4	Proto-Italic	en	in
5	Proto-Indo-European	h₁én	in