Headword and gloss are present participles in the masculine nominative plural.
An entry from the Lexicon Ambrosianum, perhaps taken from Cyril’s Lexicon (Vallicellianus E.11 or Laurentianus 57.39) or from a Cyrillian interpolated gloss (according to K.Latte): epsilon180, which is identical to this one.
The headword verb, ἐγκαθείργω , is common in the Byzantine period but rarer earlier; some instances in e.g. Josephus and Plutarch; see LSJ s.v. Cyril, Commentarius in Isaiam Prophetam 70.209, has the verb in this identical form, which strengthens Latte's arguments.