1) to be moon-struck or lunatic
2) to be epileptic
2a) epilepsy being supposed to return and increase with the increase of the moon. This meaning is doubtful as the Greeks knew nothing of epilepsy.
Part of Speech: verb
Middle or passive voice from a presumed derivative of G4582; to be moon struck, that is, crazy: - be lunatic.
|be an epileptic||23.169|
These two sites give similar information, with the definition from several dictionaries and statistics on the use of the word.
Perseus Digital Library
University of Chicago's Logion lexicon
Thayer's dictionary plus other information.
From this site's dictionary (in Italian)
Click on the first column to search for that word as a form of the root σεληνιάζομαι; click on the second column to search for that grammatical form of the root σεληνιάζομαι; click on the third column to search for that word and grammatical form; click on the total to search for the root σεληνιάζομαι.