Unspecified number subtracted from lower number (5)
![Ross](/clue/static/ross-mug.min.png)
I believe the answer is:
ether
'number' is the definition.
(anaesthetic, something which numbs)
I can't explain the remainder of the clue.
Can you help me to learn more?
(Other definitions for ether that I've seen before include "number" , "Solvent; clear sky (poet.)" , "Anaesthetic liquid; clear sky" , "Medium supposedly" , "Colourless, highly flammable liquid" .)