### Clue: A doctor with little hesitation identifying warning colour (5)
### Answer: AMBER 
 ### Explanation: Definition: warning colour
 A + MB(abbrev. for Medicinae Baccalaureus/Bachelor of Medicine, a doctor) **plus**(with) ER(a short/little word expressing one's hesitation when speaking).
Defn: …, as seen in traffic lights, to warn of the impending change to red.