Looks like it could be FABIAN, the name of a society devoted to the gradual insidious introduction of socialism, but that comma in the middle is a bit of a problem!
The Fabian Society was a political organization founded in Britain in 1884 with the aim of bringing about socialism by gradual and lawful means rather than by revolution, so Fabian fits if the answer is 6 letters instead of 3,3.
Thank you both. The published clue says 6 letters but the grid splits the answer into two by three-letter answers in top and bottom half of the crossword. Fabian is the answer.
Just in case you check back, I'm wondering which Mail on Sunday you've got because mine does'nt have that clue in any of the xwords - but 10d in the �1500 big one is FAB
Give us a clue and I'll check again
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