Where does “thiefly” come from?

thiefly (English) comes from Middle English thefly, from Middle English þef, from Old English þēof, from Proto-West Germanic þeub, from Proto-Germanic þeubaz, from Proto-Indo-European tewpó-.

thiefly (English): Like a thief; thievish; Like a thief; thievishly

Definitions

  1. Like a thief; thievish; Like a thief; thievishly

Ancestry of “thiefly”, step by step

StepLanguageWordMeaning
1Middle EnglishtheflyIn a way resembling a thief; thievishly
2Middle EnglishþefAlternative form of thef
3Old Englishþēofthief
4Proto-West Germanicþeubthief
5Proto-Germanicþeubazthief
6Proto-Indo-Europeantewpó-—
Every word from Proto-Indo-European tewpó- →Every word from Proto-Germanic þeubaz →Every word from Proto-West Germanic þeub →