Where does “thankes” come from?

thankes (Middle English) comes from Old English þancas, from Proto-Germanic þankōs, from Proto-Germanic þankaz, from Proto-Indo-European teng- — to think.

Ancestry of “thankes”, step by step

StepLanguageWordMeaning
1Old Englishþancasthanks
2Proto-Germanicþankōs—
3Proto-Germanicþankazthought; mind; consideration; remembrance;...
4Proto-Indo-Europeanteng-to think
Every word from Proto-Indo-European teng- →Every word from Proto-Germanic þankaz →Every word from Proto-Germanic þankōs →