Entry 1 sense Webster, 1913 Rhadamanthus · Rhad·a·man·thus · IPA /ˌɹæ.dəˈmæn.θəs/ 01 prop. n. One of the three judges of the infernal regions; figuratively, a strictly just judge. 1. One of the three judges of the infernal regions; figuratively, a strictly just judge.(Greek Mythol.)