An Etymological Dictionary of the German Language/fünf
fünf, card. num., ‘five,’ from MidHG. vünf, OHG. funf, also earlier finf; corresponding to Goth. fimf, OIc. fimm, AS. fif, E. five, Du. vijf, OSax. fîf. Goth. fimf, from pre-Teut. pempe, pénqe (for the permutation of Aryan q to Teut. f see Föhre, vier, Wolf); comp. Sans. páñcan, Gr. πέντε (πέμπε, πέμπτος), Lat. quinque (for *pinque), Lith. penkí, OIr. cóic, W. pimp; a common Teut. term, like all numbers from 2 to 10; the oldest form is pénqe, pénke. The attempts to discover the root with some such meaning as ‘hand,’ and to connect the word with Finger, have produced no result. The Aryan numerals are presented to us as compact forms, the origin of which is obscure. The ord. fünfte is, like all ordinals, a derivative of an old form; Goth. fimfta, OHG. fimfto, funfto, MidHG. vünfte; Du. vijfde, AS. fîfta, E. fifth. Comp. Lat. quintus for *pinctus, Gr. πέμπτος, Sans. pañcathas, Lith. pènktas.