Case Len resolved to clear up (7)

I believe the answer is:

cleanse

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'clear up' is the definition.
'cleanse' can be an answer for 'clear' (thesaurus). I am unsure of the 'up' bit.

'case len resolved' is the wordplay.
'resolved' is an anagram indicator.
'case'+'len'='caselen'
'caselen' with letters rearranged gives 'CLEANSE'.

'to' is the link.

Can you help me to learn more?

(Other definitions for cleanse that I've seen before include "Bathe" , "Free of sin" , "Purge" , "Scrub" , "Make thoroughly clean" .)

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

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