Article from the pen of singular Saint: something deep (5)
I believe the answer is:
abyss
'deep' is the definition.
(thesaurus)
'article from the pen of singular saint' is the wordplay.
'article' becomes 'a' (the indefinite article in English).
'from the pen of' becomes 'by' (as in a book being from the pen of some author).
'singular' becomes 's' (abbreviation in grammar).
'saint' becomes 's'.
'a'+'by'+'s'+'s'='ABYSS'
'something' is the link.
I am not very happy about this link. It may belong to another bit of the clue.
Can you help me to learn more?
(Other definitions for abyss that I've seen before include "Seemingly bottomless chasm" , "crevasse" , "canyon?" , "Deep pit" , "Bottomless gulf" .)