Clear article raised deepest point (5)
I believe the answer is:
nadir
'deepest point' is the definition.
(I've seen this before)
'clear article raised' is the wordplay.
'clear' becomes 'rid' (synonyms).
'article' becomes 'an' (indefinite article).
'raised' says the letters should be written in reverse (going up in a down clue).
'rid'+'an'='ridan'
'ridan' back-to-front is 'NADIR'.
(Other definitions for nadir that I've seen before include "Given lowest place" , "The lowest point of anything" , "Dinar (anag.)" , "Low-water mark" , "least successful point" .)