Where does “tha” come from?

tha (Middle English) comes from Old English þā, from Proto-Germanic þai, from Proto-Indo-European to-, from Proto-Indo-European só — this; that.

Ancestry of “tha”, step by step

StepLanguageWordMeaning
1Old Englishþāthe, those; then, when; those
2Proto-Germanicþaithey; those; nominative plural masculine of *sa
3Proto-Indo-Europeanto-it; that; the, that
4Proto-Indo-Europeansóthis; that

Words derived from “tha”

Every word from Proto-Indo-European só →Every word from Proto-Indo-European to- →Every word from Proto-Germanic þai →