Dictionary entry

ἄπειρος

G. Abbott-Smith's A Manual Greek Lexicon of the New Testament

ἄπειρος, -ον

(< ἀ- neg., πεῖρα, trial), [in LXX: Nu 14:23, Za 11:15 (אֱוִילִי), Je 2:6 (עֲרָבָה)*;]

without experience of: c. gen. rei, He 5:13 (MM, VGT, s.v.).†