Jimmy's cue ball (5)
I believe the answer is:
white
This clue might be a double definition.
'jimmy's' is the first definition.
The answer and definition can be both man-made objects as well as being singular nouns.
Maybe there's an association between them I don't understand?
'cue ball' is the second definition.
(white ball in cue sports)
Can you help me to learn more?
(Other definitions for white that I've seen before include "11's domicile" , "Pallid" , "Reflecting virtually all light" , "Colourless" , "and 9: What Bing Crosby dreamed about" .)