An Etymological Dictionary of the German Language/Annotated/heiser

heiser, adjective, ‘hoarse,’ from Middle High German heiser, ‘rough, hoarse.’ with the variant Middle High German heis, heise, Old High German heisi, heis, ‘hoarse’; Gothic *haisa- is also indicated by Anglo-Saxon hâs; in Middle English besides hǫ̂se, an abnormal hǫ̂rse occurs, whence English hoarse; so too Middle Dutch heersch, a variant of heesch (the latter also Modern Dutch); the r of the Middle High German and Modern High German derivative heiser is the widely diffused adjective suffix in bitter, lauter, hager, mager, &c. The Scandinavian háss, for the expected *heiss (Gothic *hais), also presents a difficulty. Some have attempted to connect the stem with that in hus-ten, which is impossible; hôs, hwôs, in husten, cannot, on account of the vowels, correspond to Gothic *haisa. Others, with greater reason, connect it with English to whistle, Anglo-Saxon hwistlian, and with Modern High German wispeln, ‘to whisper’ (the Teutonic root hais, hwī̆s, appears with a derivative k in Anglo-Saxon hwîskrian, Old Icelandic hvískra, ‘to whisper,’ Dutch heesch, ‘hoarse’).