An Etymological Dictionary of the German Language/Annotated/Esse
Esse, feminine (the word seems to be unknown to the Upper German dialects), ‘forge,’ from the equivalent Middle High German ęsse, Old High German ęssa, feminine, ‘chimney, hearth of a worker in metals.’ Like Old Swedish œsja, they indicate a Gothic *asjô, which is also assumed by the borrowed term, Finnish ahjo. Whether Esse is allied to Old Icelandic esja, ‘clay,’ and hence means literally ‘what is made of clay,’ remains doubtful. Its assumed connection with Old High German eit, ‘funeral pile,’ Greek αἶθος, ‘glow,’ Sanscrit root idh, ‘to burn,’ is untenable.