The headword, evidently quoted from somewhere but attested only here, is imperfect indicative middle/passive, third person singular, of the verb kataiona/w. It can have both literal (medical) and figurative senses (see LSJ s.v.); the present gloss, if correct, points to the first kind here.
Adler cites the Ambrosian Lexicon (379) as a comparandum for the entry.
cf. generally alphaiota 254.