Computer device that ran up clock! (5)
I believe the answer is:
mouse
'computer device' is the definition.
(I've seen this before)
I don't understand the remainder of the clue.
Can you help me to learn more?
(Other definitions for mouse that I've seen before include "Small rodent - computer device" , "control of computer system" , "Mickey or Minnie?" , "whose movements are captured on screen" , "Small verminous rodent" .)