Abbott-Smith Manual Greek Lexicon
διά-λεκτος (G1258)
6 διά-λεκτος , -ου, ἡ ( διαλέγομαι ), [in LXX: Da LXX 1:4 ( לָשׁוֹן ), Es 9:26 * ;] conversation, discourse, speech (Plat., Dem., al.). As in Polyb. and later writers, the language or dialect of a particular country or district: Ac 1:19 2:6 , 8 21:40 22:2 26:14 .†
G. Abbott-Smith, A Manual Greek Lexicon of the New Testament (1922) — public domain