Origin: < Yiddish < Ger schnurrer < schnurren, to whir, purr (of echoic orig.): from the sound made by musical instruments carried by beggars
See schnorrer in American Heritage Dictionary 4
Origin: Yiddish shnorer, beggar, sponger
Origin: , from shnorn, to beg
Origin: , from Middle High German snurren, to hum, whir (from the sound of the musical instrument played by beggars).