The numbers ‘twenty’ to ‘ninety’ end in ‘-ty’.
Where does this part come from?

While it’s now a suffix, ‘-ty’ stems from a Proto-Germanic noun meaning “decade, a (group of) ten”.

For example, ‘forty’ comes from *fedwōr tegiwiz, literally “four tens”.

Only Icelandic, Swedish, and Elfdalian have preserved this word as a noun.

Click my new graphic to learn all about ‘-ty’ and its relatives:

@yvanspijk @secbox
Slightly related story you may find interesting: I grew up in Saarland, a resource-rich border area which association changed multiple times between France & Germany after several wars. People there speak German, with an accent close to Luxembourgish. My grandma used the word "dix", just like the French word for ten (but pronounced diggs, not diss as in French) to say "often". And "dixer" (diggser) for "more often".
Miles away from "oft" or "häufig" in German.
@musevg @secbox Ah, yes, that word is related to German 'dick' ("fat"). In the southern regional languages of the Netherlands, they use 'dik(s)' to say "often" as well. It comes from a medieval combination with 'wile' (now German 'Weil(e)'), meaning "many times".
@yvanspijk @secbox
Whoa, that's interesting! So it's not related to French dix but to southern Netherlands diks? Amazing!