Where does “impugnable” come from?

impugnable (Spanish) comes from Spanish impugnar, from Latin impugnō, from Latin im-, from Latin īn-, from Latin în, from Latin en, from Proto-Italic en, from Proto-Indo-European h₁én — in.

impugnable (Spanish): impugnable

Definitions

impugnable

Ancestry of “impugnable”, step by step

Step	Language	Word	Meaning
1	Spanish	impugnar	to contest
2	Latin	impugnō	to attack, fight against
3	Latin	im-	Alternative form of in-; form of "in"; in
4	Latin	īn-	un-, non-, not
5	Latin	în	in, at, on, upon, from (space)
6	Latin	en	lookǃ beholdǃ; reallyǃ?; come onǃ
7	Proto-Italic	en	in
8	Proto-Indo-European	h₁én	in

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