The definition of a disaster is an event, often sudden, that causes great damage or devastation.
(noun)An example of disaster is a tsunami.
See disaster in Webster's New World College Dictionary
noun
Origin: OFr desastre < It disastro < L dis- + astrum < Gr astron (see astral), star: from astrological notions: cf. ill-starred
See disaster in American Heritage Dictionary 4
noun
Origin:
Origin: French désastre
Origin: , from Italian disastro
Origin: : dis-, pejorative pref. (from Latin dis-; see dis- )
Origin: + astro, star (from Latin astrum, from Greek astron; see ster-3 in Indo-European roots)
.Learn more about disaster