Where does “lag-” come from?

lag- (Proto-Albanian) comes from Irish lag, from Old Irish lác, from Proto-Celtic laggos, from Proto-Indo-European (s)leh₁g- — weak, feeble; weak, faint.

Ancestry of “lag-”, step by step

lag- traces back through two separate lines of ancestry.

via Irish lag

StepLanguageWordMeaning
1Irishlagweak
2Old Irishlácweak, feeble
3Proto-Celticlaggos
4Proto-Indo-European(s)leh₁g-weak, feeble; weak, faint

via Proto-Indo-European legʰ-

StepLanguageWordMeaning
1Proto-Indo-Europeanlegʰ-to lie

Words derived from “lag-

Every word from Proto-Indo-European (s)leh₁g-Every word from Proto-Celtic laggosEvery word from Old Irish lác