Where does “must” come from?

must (Finnish) comes from English must, from Old English mōste, from Old English mōtan, from Proto-West Germanic *mōtan, from Proto-Germanic mōtaną, from Proto-Indo-European mōd-, from Proto-Indo-European med- — to measure; to give advice; healing.

must (Finnish): must something mandatory or required

Definitions

  1. must something mandatory or required

Ancestry of “must”, step by step

must traces back through two separate lines of ancestry.

via English must

StepLanguageWordMeaning
1EnglishmustTo do with certainty; To do as a requirement;...
2Old Englishmōstehad to
3Old Englishmōtanto be allowed, be able to, have the opportunity...
4Proto-West Germanic*mōtanto be allowed, to be permitted to, may
5Proto-Germanicmōtanąto be allowed, to be permitted to, may
6Proto-Indo-Europeanmōd-to permit, make able
7Proto-Indo-Europeanmed-to measure; to give advice; healing

via Finnish musta

StepLanguageWordMeaning
1Finnishmustablack; black horse; Elative singular form of...
2Finnish-ntääFront vowel variant of -ntaa
Every word from Proto-Indo-European med-