### Clue: Fool one in three names with chicanery, finally (5)
### Answer: NINNY 
 ### Explanation: Definition: Fool
 I(Roman numeral for "one") **contained in**(in) NNN(3 x abbrev. for "name") **plus**(with) **last letter of**(…, finally) "chicanery".
Defn: A foolish and weak person.