undeadlinessEtymologyCalque of Middle English undedlynesse (or, in some cases, a continuation rather than a calque), from Old English undēadlīcnes (“immortality”); equivalent to undeadly + -ness; compare German Unsterblichkeit, a similarly formed compound.undeadliness means The condition of not being susceptible to death; immortality. Lexicurio rates it Sui generis — a strength score of 87 out of 100.nounThe condition of not being susceptible to death; immortality.“Although the holy fathers, who were before us, very certainly knew about that which thou formerly askedst; that is, about the undeadliness of men's souls, which was very clear in this that they naught doubted, […]”