Without cease (7)
I believe the answer is:
endless
'without cease' is the definition.
('cease' can be 'end' (synonyms) so maybe 'without cease' can be ''endless')
This is all the clue.
(Other definitions for endless that I've seen before include "'Eternal, perpetual (7)'" , "Eternal - unbroken" , "no boundaries" , "Unceasing" , "Sister of Aaron (Exodus)" .)