caducity

Caducity derives by way of the French caduc, meaning "transitory," from the Latin caducus, meaning "tending to fall," a product of the verb cadere, meaning "to fall." Words that share the "cadere" root with "caducity" include "accident," "coincide," "cadaver," and "chance." "Caducity" usually refers to the fleeting or perishable nature of something. More specifically, it can refer to the perishable nature of cognitive abilities and can be used as a synonym of senility. Both senses of the word first appeared in English in the second half of the 18th century.