An Etymological Dictionary of the German Language/empor
empor, adv., ‘upwards, aloft,’ from MidHG. enbor, enbore, adv., ‘into or in the heights’; OHG. inbore, in bore, with the same meaning; a combination of the prep. in with the dat. of OHG. and MidHG. dor, ‘upper space’ (OHG. also ‘summit’), the origin of which is obscure. It scarcely belongs to the root ber, ‘to carry’ (in Bahre); more probably to empören. The p of the ModHG. word is based on an early ModHG. medium form entbôr, from which entpor, empor, must have been produced.