μητρόπολιν (metropolin)
μητρόπολιν is an Ancient Greek form of μητρόπολις, meaning “mother city”. It is the accusative singular feminine noun.
Found 65 times in the Ancient Greek texts on Socratos.
Where it is used
Thucydides, History of the Peloponnesian War 1.24.6: οἱ δὲ ἐν τῇ πόλει ὄντες Ἐπιδάμνιοι ἐπειδὴ ἐπιέζοντο, πέμπουσιν ἐς τὴν Κέρκυραν πρέσβεις ὡς μητρόπολιν οὖσαν, δεόμενοι μὴ σφᾶς περιορᾶν φθειρομένους, ἀλλὰ τούς τε φεύγοντας ξυναλλάξαι σφίσι καὶ τὸν τῶν βαρβάρων πόλεμον καταλῦσαι.
Strabo, Geography 12.3.11: … αὶ τῶν καταλυσάντων Ῥωμαίων ἐκεῖνον. ὁ δὲ Εὐπάτωρ καὶ ἐγεννήθη ἐκεῖ καὶ ἐτράφη· διαφερόντως δὲ ἐτίμησεν αὐτὴν μητρόπολίν τε τῆς βασιλείας ὑπέλαβεν. ἔστι δὲ καὶ φύσει καὶ προνοίᾳ κατεσκευασμένη καλῶς· ἵδρυται γὰρ ἐπὶ αὐχένι χερρονή …
All forms of μητρόπολις (declension table)
Source: Socratos (socratos.org), a free reader for Ancient Greek and Latin. Grammar from the Perseus Treebank and Morpheus; dictionary entries from Liddell-Scott-Jones, A Greek-English Lexicon (Perseus Digital Library, CC BY-SA). Counts are from the texts on Socratos.