Where does “ümumilikdə” come from?

ümumilikdə (Azerbaijani) comes from Azerbaijani -də, from Proto-Turkic *-de.

Ancestry of “ümumilikdə”, step by step

StepLanguageWordMeaning
1Azerbaijani-dəLocative suffix
2Proto-Turkic*-de—
Every word from Proto-Turkic *-de →Every word from Azerbaijani -də →