Enormous disaster struck it (7)

I believe the answer is:

titanic

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'enormous' is the definition.
(I've seen this before)

I can't explain the rest of the clue.

(Other definitions for titanic that I've seen before include "Of enormous size, like the stricken liner" , "like Oceanus" , "Colossal, liner" , "Very big and powerful" , "Ill-fated vessel" .)

I've seen this clue in The Globe and Mail.

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