Allow nurses to depart — it could be a slippery slope? (8)
I believe the answer is:
gradient
'slope?' is the definition.
(I've seen this before)
'allow nurses to' is the wordplay.
'allow' becomes 'grant' (synonyms).
'nurses' indicates putting letters inside (nurse can mean to hold onto or harbour).
'to' becomes 'die' (I can't justify this - if you can you should give a lot more credence to this answer).
'grant' enclosing 'die' is 'GRADIENT'.
'depart it could be a slippery' acts as a link.
This may not be right. Some or all of it may belong to another bit of the clue.
Can you help me to learn more?
(Other definitions for gradient that I've seen before include "Level of steepness" , "Third OT book" , "Angle of slope" , "Bank" , "Rise" .)