Russian среда

← Old Church Slavonic срѣда (borrowed)

← Old East Slavic середа (cognate)

← Old East Slavic третииникъ (mention)

← Russian середа́ (doublet)

← Russian сре́дний (link)

← Russian среди́ (link)

← Proto-Slavic *serda (derived)

→ Ingrian sereta (borrowed)