The headword is masculine nominative plural, presumably quoted from somewhere but attested only here and, according to Adler, the Ambrosian Lexicon. The form appears to be a perfect active participle but has no reduplication, and in any case the perfect active of dama/zw (cf. delta 1309) seems to be rare: see LSJ s.v.
For the perfect middle/passive, see delta 154 and delta 155.