Fatal

a.	1.	Proceeding from, or appointed by, fate or destiny; necessary; inevitable. These thing are fatal and necessary. - Tillotson. It was fatal to the king to fight for his money. - Bacon.
	2.	Foreboding death or great disaster. That fatal screech owl to our house That nothing sung but death to us and ours. - Shak.
	3.	Causing death or destruction; deadly; mortal; destructive; calamitous; as, a fatal wound; a fatal disease; a fatal day; a fatal error.

Adj.	1.	fatal - bringing death Antonyms: nonfatal - not bringing death; "nonfatal heart attack"
	2.	fatal - having momentous consequences; of decisive importance; "that fateful meeting of the U.N. when...it declared war on North Korea"- Saturday Rev; "the fatal day of the election finally arrived" Synonyms: fateful
	3.	fatal - (of events) having extremely unfortunate or dire consequences; bringing ruin; "the stock market crashed on Black Friday"; "a calamitous defeat"; "the battle was a disastrous end to a disastrous campaign"; "such doctrines, if true, would be absolutely fatal to my theory"- Charles Darwin; "it is fatal to enter any war without the will to win it"- Douglas MacArthur; "a fateful error" Synonyms: calamitous, disastrous, fateful, black
	4.	fatal - controlled or decreed by fate; predetermined; "a fatal series of events" Synonyms: fateful

(programming)

fatal - Resulting in termination of the program.

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