Neville17
First, there are 5 letters in the solution, not the 6 you have above. Second, "cycling" often indicates that the wordplay inication must be cycled (eg, letters moved to the front or back). Defn is 1st word.
Chrise
As to theme, there is a word that crops up 3 times in the clues. There are (I think) 10 types of this word in the solutions - 9 in the downs and 1 in the acrosses.
Hi Rog, I agree with your 10 theme item (split 9 + 1).
I was surprised by 25d. The term in question is widely regarded as derogatory. Its use is banned by the Associated Press which may explain why not familiar in the US.