Dictionary entry

βασίλειος

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

βασίλειος, -ον (also -α, -ον;

< βασιλεύς), [in LXX; Ex 19:6, De 3:10 (מַמְלָכָה), Ex 23:22, Wi 18:15, III Mac 3:28, IV Mac 3:8*;]

royal: I Pe 2:9^(LXX) (v. Hort, in l.).†