An Etymological Dictionary of the German Language/Schnur
Schnur (1.), f., ‘string, cord, line,’ from MidHG. and OHG. snuor, f., ‘string, bond, rope’; comp. Goth. snôrjô, f., ‘basket, basket-work,’ OIc. snœre, ‘twisted cord,’ Du. snoer, ‘string’; allied to the Aryan root snô, snē̆, ‘to plait’ (comp. nähen), with which AS. snô-d, ‘fillet,’ as well as OIr. snáth, ‘thread,’ is connected.
Schnur (2.), f. (mostly obsolete in the dials. e.g., Swiss and Bav.), ‘daughter-in-law,’ from the equiv. MidHG. snur (snuor), OHG. snura (snora), f.; with this is connected the equiv. derivative MidHG. snürche (OHG. *snurihha). Corresponding to MidLG. snore, AS. snoru, MidE. snore (obsolete in E.), OFris. snore, OIc. snor, snør, ‘daughter-in-law’ (Goth. *snuzô, f., is by chance not recorded). A common Aryan term for ‘daughter-in-law’ (comp. also other terms common to Aryan for degrees of relationship, such as Sohn, Tochter, &c.), in the Aryan form snusã (Sans. snušã, OSlov. snŭcha), and Aryan snusū̆s, in Lat. nurus (for snusus), Gr. νυός (for *σνυσύς). Aryan snusã, wife,’ has been regarded as a derivative of Aryan sū̆nū̆-, ‘son,’ on account of Söhnerin, the Suab. term for Schnur.