Origin of schatzi

1955–60; < German Schatzi (orig. dial., especially Swiss G), equivalent to Schatz treasure (Middle High German scha(t)z, Old High German scaz property, piece of money; see sceat) + -i diminutive suffix (Middle High German -în; see -en5) Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

Word Origin and History for schatzi

"German girlfriend," from German Schatzi, diminutive of Schatz, a term of endearment for a woman, literally "treasure," from Proto-Germanic *skatta- (cf. Dutch schat "treasure," Gothic skatts "piece of money, money"), originally "cattle."

Online Etymology Dictionary, © 2010 Douglas Harper