Fertiliser chemical - some spurn it religiously (5)
I believe the answer is:
nitre
'fertiliser' is the definition.
(I've seen this before)
'some spurn it religiously' is the wordplay.
'some' says the answer is hidden in the clue (some parts of the word are used).
'NITRE' can be found hidden inside 'spurn it religiously'.
'chemical' acts as a link.
I am not very happy about this link. It may be part of another bit of the clue.
Can you help me to learn more?
(Other definitions for nitre that I've seen before include "Sodium nitrate" , "Also known as salt-petre" , "explosive ingredient" , "Gunpowder ingredient" , "constituent of gunpowder" .)