The most common and most likely answer to this crossword clue is the 7 letter word TREASON
I've seen this crossword clue in Independent
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More clues leading to the result TREASON
- No tears about disloyalty
- Agent's ultimate motivation is betrayal
- Betrayal Tristan’s principal motivation
- One needs time and motivation for such a crime
- Senator suffering great betrayal
- Cause supporting activist's last crime
- Court at the end presented with motive for crime
- The principal inducement for betrayal
- . Very concerning having to cover up a crime
- Ultimately worst motive for crime
Buddy explains!
The straight part
We know that "of side in lost cause (7)" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case of side in lost cause (7) = treason.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 TREASON mean?
TREASON noun- The crime of betraying one’s own country.
- An act of treachery, betrayal of trust or confidence.