Where does “adren-” come from?

adren- (English) comes from English ad-, from Latin ad-, from Latin īn-, from Latin în, from Latin en, from Proto-Italic en, from Proto-Indo-European h₁én — in.

Ancestry of “adren-”, step by step

StepLanguageWordMeaning
1Englishad-near, at; toward, to, tendency, or addition
2Latinad-to; usually prefixed to verbs, in which cases it...
3Latinīn-un-, non-, not
4Latinînin, at, on, upon, from (space)
5Latinenlookǃ beholdǃ; reallyǃ?; come onǃ
6Proto-Italicenin
7Proto-Indo-Europeanh₁énin

Words derived from “adren-”

Every word from Proto-Indo-European h₁én →Every word from Latin īn- →Every word from Latin ad- →