Where does “infantile” come from?

infantile (Italian) comes from Latin infantilis, from Latin īnfāns, from Latin īn-, from Latin în, from Latin en, from Proto-Italic en, from Proto-Indo-European h₁én — in.

infantile (Italian): infantile; infantile puerile, childish, babyish

Definitions

infantile; infantile puerile, childish, babyish

Ancestry of “infantile”, step by step

Step	Language	Word	Meaning
1	Latin	infantilis	pertaining to an infant; infantile
2	Latin	īnfāns	speechless, inarticulate
3	Latin	īn-	un-, non-, not
4	Latin	în	in, at, on, upon, from (space)
5	Latin	en	lookǃ beholdǃ; reallyǃ?; come onǃ
6	Proto-Italic	en	in
7	Proto-Indo-European	h₁én	in

Words derived from “infantile”

infantilità
infantilmente
infantilismo

Every word from Proto-Indo-European h₁én →Every word from Latin īn- →Every word from Proto-Italic en →