Where does “impugnandus” come from?

impugnandus (Latin) comes 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.

impugnandus (Latin): which is to be attacked

Definitions

which is to be attacked

Ancestry of “impugnandus”, step by step

Step	Language	Word	Meaning
1	Latin	impugnō	to attack, fight against
2	Latin	im-	Alternative form of in-; form of "in"; in
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

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