Where does “undereye bag” come from?

undereye bag (English) comes from English undereye, from English Eye, from English -some, from Middle English -som, from Old English sum, from Proto-West Germanic *sum, from Proto-Germanic sumaz, from Proto-Indo-European sem- — together, one.

Ancestry of “undereye bag”, step by step

undereye bag traces back through two separate lines of ancestry.

via English undereye

StepLanguageWordMeaning
1EnglishundereyeUnder the eye; The area of skin immediately under...
2EnglishEyeA place name
3English-someCharacterized by some specific condition or...
4Middle English-somsome; having a specific quality
5Old Englishsumsome
6Proto-West Germanic*sumsome
7Proto-Germanicsumazsome (one), a certain (one)
8Proto-Indo-Europeansem-together, one

via English bag

StepLanguageWordMeaning
1EnglishbagA flexible container made of cloth, paper,...
2Middle EnglishbaggeA fabric container; a bag, sack, pouch, purse, or...
3Old Norsebaggibag, pack, satchel, bundle
4Proto-Indo-Europeanbʰak-
Every word from Proto-Indo-European sem-Every word from Proto-Germanic sumazEvery word from Proto-West Germanic *sum
undereye bag — Etymology, Origin & Word History | Etymology Explorer