Others tie up back in amenities facility (8)
I believe the answer is:
restroom
'amenities facility' is the definition.
I know nothing about this answer so I cannot judge whether it can be defined by this definition.
'others tie up back' is the wordplay.
'others' becomes 'rest' (I've seen this in another clue).
'tie up' becomes 'moor' (as in mooring a boat).
'back' says the letters should be written backwards.
'moor' written backwards gives 'room'.
'rest'+'room'='RESTROOM'
'in' acts as a link.
Can you help me to learn more?
(Other definitions for restroom that I've seen before include "Where some may have recovered" , "John" .)