Noun

(en noun)

An unexpected natural or man-made catastrophe of substantial extent causing significant physical damage or destruction, loss of life or sometimes permanent change to the natural environment.

* {{quote-magazine, date=2013-06-29, volume=407, issue=8842, page=28, magazine=(The Economist)

, title= High and wet , passage=Floods in northern India, mostly in the small state of Uttarakhand, have wrought disaster on an enormous scale. The early, intense onset of the monsoon on June 14th swelled rivers, washing away roads, bridges, hotels and even whole villages. Rock-filled torrents smashed vehicles and homes, burying victims under rubble and sludge.}}

An unforeseen event causing great loss, upset or unpleasantness of whatever kind.

*{{quote-book, year=1959, author=(Georgette Heyer), title=(The Unknown Ajax), chapter=1

, passage=And no use for anyone to tell Charles that this was because the Family was in mourning for Mr Granville Darracott […]: Charles might only have been second footman at Darracott Place for a couple of months when that disaster occurred, but no one could gammon him into thinking that my lord cared a spangle for his heir.}}

* 2003 ,

A nod means good, two nods; very good. And then there's the pursing of the lips: disaster .

Noun

(uncountable) Susceptibility to attack or injury; the state or condition of being weak or poorly defended.

The country recognized their defence vulnerability after an airplane landed in front of the central square without any consequences.

(countable) a specific weakness in the protections or defences surrounding someone or something.

(computing) a weakness which allows an attacker to reduce a system's security