### Clue: Certainly less than 50% (3,4)
### Answer: NOT HALF 
 ### Explanation: Definition: Certainly,less than 50%
 Double defn: 1st: Indeed,surely,Certainly, as in "I agree he's not half stupid". But "not half" also means "not really", as in "he's not half clever enough to do that". One of those Janus (two-faced god of war) words/phrases that can take opposite meanings.