An Etymological Dictionary of the German Language/Abend
Abend, m., ‘evening,’ from the equiv. MidHG. âbent (âbunt); OHG. âband, m.; corresponding to OSax. âƀand, Du. avond, AS. œ̂fen, ‘evening,’ whence E. eve; also the deriv. AS. œ̂fning, E. evening (comp. morning); OIc. aptann; similarly Goth. andanahti, orig. sense ‘forenight,’ and sagqs, lit. ‘setting.’ The SEurop. term corresponding to Gr. ἕσπερος, Lat. vesper, is non-Teut. (comp. West and Winter). A verb aben (ooben), ‘to grow dusk,’ adduced from the Swiss dialects to explain Abend, can be none other than a later derivative of Abend. Moreover, Abend (base êp-) can scarcely be connected with ab (base apo), as if Abend were the waning period of the day. According to old Teut. notions, the evening was regarded rather as the beginning of the following day. See Sonnabend and Fastnacht.