twēntiġ
From Proto-Germanic *twaintigaz, *twai tigiwiz. Compare Old Frisian and Old English twēntiġ, Old High German zweinzug, Old Norse tuttugu.
twentig
From Proto-Germanic *twaintigaz, *twai tigiwiz, a compound of *twai (compare two) and *tigiwiz, plural of *teguz. Compare Old Frisian and Old Saxon twentig, Old High German zweinzug, Old Norse tuttugu.