What it's a relief to be - from Friday! (3)
I believe the answer is:
rid
'what it's a relief to' is the definition.
I can't judge whether this defines the answer.
'from friday' is the wordplay.
'from' says the answer is hidden in the clue.
'RID' is hidden in the letters of 'friday'.
'be' is the link.
Can you help me to learn more?
(Other definitions for rid that I've seen before include "Free from something unpleasant" , "Free, disencumber" , "Disabuse" , "Clear, remove" , "Free (someone of something unwanted)" .)