Marriage of two OT characters meeting resistance, calm (7)

I believe the answer is:

relieve

'calm' is the definition.
(thesaurus)

I cannot understand how the rest of the clue works.

(Other definitions for relieve that I've seen before include "Release from duty" , "help" , "Soothe" , "Alleviate, assuage" , "Lighten a burden or raise a seige" .)

I've seen this clue in The Times.

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