Shelter from a terrible earthquake (3)
I believe the answer is:
lee
'shelter' is the definition.
(as in lee side, the side sheltered from wind)
'from a terrible earthquake' is the wordplay.
'from' indicates the answer is hidden within the clue.
'LEE' is hidden within 'terrible earthquake'.
(Other definitions for lee that I've seen before include "Commander of the Confederate States Army in the American Civil War" , "The side that's sheltered from the wind" , "Shelter" , "The sheltered side - of Cork's river?" , "Protection" .)