### Clue: Centenarian leader and topless coquette don't do it any more! (5)
### Answer: CEASE 
 ### Explanation: Definition: don't do it any more!
 **1st letter of**(… leader) "Centenarian" **plus**(and) "tease"(an example of which is a coquette/a female flirt) **minus ****its 1st letter**(topless …, in a down clue).
Defn: …/Stop!
Answer: As in "… and desist".