Where does “közöttük” come from?

közöttük (Hungarian) comes from Hungarian között, from Hungarian -ött, from Hungarian -ö-, from Hungarian -d, from Middle Welsh -nt — 3rd person plural verb ending.

Ancestry of “közöttük”, step by step

Step	Language	Word	Meaning
1	Hungarian	között	between, among
2	Hungarian	-ött	-ed, -t; in
3	Hungarian	-ö-	linking vowel
4	Hungarian	-d	your; Used in the second-person singular definite...
5	Middle Welsh	-nt	3rd person plural verb ending

Every word from Middle Welsh -nt →Every word from Hungarian -d →Every word from Hungarian -ött →