The most common and most likely answer to this crossword clue is the 12 letter word DILAPIDATION
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More clues leading to the result DILAPIDATION
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The straight part
We know that "ruin" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case ruin = dilapidation.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does DILAPIDATION mean?
DILAPIDATION noun- The state of being dilapidated, reduced to decay, partially ruined.
- The act of dilapidating, damaging a building or structure through neglect or intentionally.
- Ecclesiastical waste: impairing of church property by an incumbent, through neglect or intentionally.
- (in the plural) Money paid at the end of an incumbency by the incumbent or his heirs for the purpose of putting the parsonage etc. in good repair for the succeeding incumbent.