dwindle (v.)youdaoicibaDictYouDict
1590s, apparently diminutive and frequentative of Middle English dwinen "waste away, fade, vanish," from Old English dwinan, from Proto-Germanic *dwinan (cognates: Dutch dwijnen "to vanish," Old Norse dvina, Danish tvine, Low German dwinen), from PIE *dheu- (3) "to die" (see die (v.)). Related: Dwindled; dwindling.
swindle (v.)youdaoicibaDictYouDict
1782, back-formation from swindler "cheater." Related: Swindled; swindling. As a noun, "act of swindling," from 1833.
swindler (n.)youdaoicibaDictYouDict
1774, from German Schwindler "giddy person, extravagant speculator, cheat," from schwindeln "to be giddy, act extravagantly, swindle," from Old High German swintilon "be giddy," frequentative form of swintan "to languish, disappear;" cognate with Old English swindan, and probably with swima "dizziness." Said to have been introduced in London by German Jews c. 1762.