The only one I can think of is "pronunciation", but that one is more related to the way you say it rather than to the way you write it.
2You can always just ask, “ Is this right?”– JimMar 16, 2017 at 11:14
@Jim Whether something is right is quite a different concept to grammatical correctness.– LawrenceMar 16, 2017 at 12:11
@Lawrence - Yes of course, but if someone is wanting to know if something is grammatically correct but doesn’t want to use the “normal words” for that then “right” is probably sufficient for their purposes.– JimMar 16, 2017 at 12:13
@Jim If the context constrains the term sufficiently, that's fine.– LawrenceMar 16, 2017 at 12:15
@Lawrence - yeah it was just a comment.– JimMar 16, 2017 at 12:17
"The state or quality of being grammatical," or "grammatical correctness" is known as:
And Mithrandir has provided the adjective form in Mithrandir's answer above.
Grammatical correctness is also known as grammaticality.
Grammatical correctness as related to the way you write is also known as grammaticality.
"In...linguistics...a grammaticality judgement...is based on whether the sentence is produced and interpreted in accordance with the rules and constraints of the relevant grammar" ("Grammaticality," Wikipedia).
"The grammaticality of a sentence is things that conform to the linguistic rules or syntactic rules (Fromkin and Rodman 1998:106) ("The Grammaticality versus The Acceptability," Linguistik.)
grammatical without 'correctness'?
of or relating to grammar:
conforming to standard usage:
dictionary.com gives 'antigrammaticalness, noun' as a related word, so I assume that if you remove the 'anti' that gives 'grammaticalness', which should work as a noun.