#0057 ἄγνωστος agnostos {ag'-noce-tos'}

 from G0001 (as negative particle) and G1110; TDNT - 1:119,18; adj

—Greek Word Study (Transliteration-Pronunciation Etymology & Grammar)

 1) unknown, forgotten

 ++++
 Epimenides, a certain Cretan, came to Athens to stop a plague. He
 offered a sheep on alters the born no name of no god but to the
 "unknown god". At least one of the alters survived to Paul's day.

—Thayer's (New Testament Greek-English Lexicon)

—Strong's (Greek Dictionary of the New Testament)

—NAS Exhaustive Concordance of the Bible with Hebrew-Aramaic and Greek Dictionaries

 AV - unknown 1; 1

—Exhaustive Concordance (KJV Translation Frequency & Location)