An Etymological Dictionary of the German Language/Dotter
Dotter (1.), m. and n., ‘yolk,’ from the equiv. MidHG. toter, OHG. totoro, tutar-ei; the ModHG. word seems to have a LG. initial sound. Corresponds to OSax. dŏdro, Du. dojer, AS. dydring, ‘yolk’; a pre-Teut. term for the ‘yolk of an egg’ (see also Ei). AS. dott, m., ‘point, spot,’ E. dot are, on account of LG. dott, dötte, ‘yellow part of the egg,’ to be derived from the same Aryan stem dhut; the orig. sense of Dotter may lave been, therefore, ‘point in the egg.’ The E. term yolk, AS. geolca, is lit. ‘yellow part,’ from AS. geolo, equiv. to E. yellow. In OIc. blóme, ‘yolk.’
Dotter (2.), m., from the equiv. MidHG. toter, m., ‘gold-pleasure’; comp. MidE. doder, E. dodder (‘toad-flax’); Dan. dǫdder, Swed. dǫdra. Perhaps allied to Dotter (1.), so that the plant was named from its colour (or from the similarity of its seeds to the yolk of an egg?).