An Etymological Dictionary of the German Language/Annotated/weichen
weichen, verb, ‘to yield, give away, waver,’ from the equivalent Middle High German wîchen, Old High German wîhhan, strong verb; corresponding to the equivalent Old Icelandic ýkva, víkja, Old Saxon wîkan, Dutch wijken. The Teutonic root wī̆q, ‘to yield,’ literally ‘to make room for some one, give way,’ appears also in Wechsel and weich. Its earlier form wī̆g (in Sanscrit vij, ‘to yield, flee’) is a variant of wī̆k, which is indicated by Latin vices, ‘change,’ and especially by Greek εἴκω, ‘to yield.’ Compare also Woche.