c. 1400, past-participle adjective from fall (v.). Used figuratively for "morally ruined" by 1620s, from the verb in the sense "yield to temptation" (especially in reference to women and chastity), attested from c. 1200. Meaning "those who have died" attested by 1765. Fallen angel is from 1680s; fallen woman by 1748.
fallen leaves covered the forest floor
sat on a fallen tree trunk
a fallen building
a fallen woman
to honor fallen soldiers
falderol
fall
fallacious
fallacy
fallback
fallen
fallibility
fallible
falling
Fallopian
fallout