Here's a breakdown:
* Syntax: The rules governing the arrangement of words and phrases in a sentence.
* Syntactical: Relating to or concerned with syntax.
Examples:
* "The syntactical structure of the sentence is unusual." (meaning the sentence is grammatically unusual)
* "The author uses complex syntactical patterns to create a sense of ambiguity." (meaning the author uses complex grammar to make the meaning unclear)
* "He made a syntactical error in his essay." (meaning he made a grammatical error)
Essentially, syntactical focuses on how words are put together, rather than their individual meanings.