### Clue: Fostered one put stone finally in giant-killing weapon after run up? (9)
### Answer: NURSELING 
 ### Explanation: Definition: Fostered one
  [E(last letter,finally of "stone") **contained in**(put…in) SLING(giant-killing weapon used in the biblical contestn of David vs. Goliath)] **placed after**(after) **reversal of**(up, in a down clue) RUN