Lexical Definition

‎σεληνιάζομαι‎ selēniázomai (sel-ay-nee-ad'-zom-ahee) be epileptic G:V
middle voice or passive from a presumed derivative of ‎σελήνη‎

be a lunatic.

Usage: 2 forms in 2 verses
Form Translated As     In Verse(s)
σεληνιαζομένουσ those being epileptic Matt.4.24
σεληνιάζεται he is epileptic Matt.17.15

Abbott-Smith

*† σεληνιάζω (< σελήνη), act, in Manetho (Carm., 4, 81), in NT depon. -ομαι,
to be moonstruck, i.e. epileptic (epilepsy being supposed to be influenced by the moon): Mt 4:24 17:15.†

Abbott-Smith References

Book Refs
Matthew 4:24 · 17:15

Liddell-Scott-Jones

σεληνιάζομαι-ιάζομαι,

passive, to be moonstruck, i.e. epileptic, [NT+2nd c.AD+]

__2 to be sublunar, i.e. subject to change and decay, -ομένης τῆς φύσεως[Refs 5th c.BC+]

LSJ Scripture Refs: Matt.4.24