From a hypothetical Proto-Tocharian*w'īkän, from Proto-Indo-European*h₁wih₁ḱm̥t or *h₁wih₁ḱm̥ti, from *dwi(h₁)dḱm̥ti (cognate with Latin vīgintī, Ancient Greek εἴκοσι(eíkosi), Doric ϝείκατι(weíkati), Sanskrit विंशति(viṃśati), Avestan [script needed](vīsaiti), Ossetian инсӕй(insæj), Armenian քսան(kʿsan), Albanian (një)zet, Welsh ugain). Compare Tocharian A wiki.