The most common and most likely answer to this crossword clue is the 8 letter word ADULTERY
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More clues leading to the result ADULTERY
- Infidelity upsets true lady
- Infidelity hurt true lady
- Qualities oddly forgotten entering a boring affair
- This upset true lady
- On leaving Luton, ready to travel, playing away
- Ranting rudely at many a minister’s practice
- Cheating male ultimately in wild rut with lady
- Cheating of French Lieutenant visionary accepts
- Cheating unrestrainedly, letters of sinner hidden before messing around
- Raging rudely at illicit sex
Buddy explains!

The straight part
We know that "many a (cabinet?) minister’s practice" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case many a (cabinet?) minister’s practice = adultery.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 ADULTERY mean?
ADULTERY noun- Sexual intercourse by a married person with someone other than their spouse.
- Lewdness or unchastity of thought as well as act, as forbidden by the seventh commandment.
- Faithlessness in religion.
- The fine and penalty formerly imposed for the offence of adultery.
- The intrusion of a person into a bishopric during the life of the bishop.
- (political economy) Adulteration; corruption.
- Injury; degradation; ruin.