An Etymological Dictionary of the German Language/Annotated/stark
stark, adjective, ‘strong,’ from Middle High German starc (and starch), Old High German starc (and starah), adjective, ‘strong, vigorous, big’; corresponding to Old Saxon stark, Dutch sterk, Anglo-Saxon stearc, English stark, Old Icelandic sterkr. To the same Teutonic root stark belong by a different gradation Gothic gastaúrknan, ‘to become parched, wither away,’ Old Icelandic storkna, ‘to curdle,’ Old High German storchanên, ‘to become fixed, hard’; hence perhaps ‘fixed’ is the primitive meaning of the root. Lithuanian strėgti, ‘to stiffen, become numb,’ and Modern Persian suturg (base *stṛga), ‘strong,’ are primitively allied. Derivative Modern High German Stärke, feminine, ‘starch’ (note the English word).