Where does “badthink” come from?

badthink (English) comes from English bad, from Middle English bad, from Old English bæd, from Old English biddan, from Proto-West Germanic biddjan, from Proto-Germanic bidjaną, from Proto-Indo-European bʰidʰ-, from Proto-Indo-European bʰeydʰ- — to compel, force; to trust.

Ancestry of “badthink”, step by step

badthink traces back through two separate lines of ancestry.

via English bad

StepLanguageWordMeaning
1EnglishbadUnfavorable; negative; not good; Not suitable or...
2Middle Englishbad
3Old Englishbædfirst/third-person singular preterite of biddan
4Old Englishbiddanto ask; to beg
5Proto-West Germanicbiddjanto ask, to make a request
6Proto-Germanicbidjanąto make a request; to ask; to request, ask
7Proto-Indo-Europeanbʰidʰ-to command; pot, bucket, barrel
8Proto-Indo-Europeanbʰeydʰ-to compel, force; to trust

via English think

StepLanguageWordMeaning
1EnglishthinkTo ponder, to go over in one's head; To...
2Middle EnglishthinkenTo think, ponder; to deduce, figure out; to...
3Old Englishþyncanto seem
4Proto-Germanicþunkijanąto seem, to appear
Every word from Proto-Indo-European bʰeydʰ-Every word from Proto-Indo-European bʰidʰ-Every word from Proto-Germanic bidjaną