Religious aid on which one can count (6)
I believe the answer is:
rosary
This could be a double definition.
'religious aid on which one' is the first definition.
Although both the answer and definition are singular nouns, I cannot understand how one could define the other.
'can count' is the second definition.
The answer and definition can be both man-made objects as well as being singular nouns.
Maybe you can see a link between them that I don't see?
(Other definitions for rosary that I've seen before include "Series of prayers" , "believer can count on it" , "RC beads" , "String of prayer beads" , "Flower garden" .)