### Clue: Banker reportedly supports railway that keeps time (9)
### Answer: METRONOME 
 ### Explanation: Definition: that keeps time
 **Homophone of**(… reportedly) "gnome"(a banker regarded as having sinister influence in financial matters, as in "the Gnomes of Zurich") **placed below**(supports, in a down clue) METRO(an underground railway system, eg. the Metro in Paris).
Defn: The device ….