Syntax in general is word order and sentence structure. Syntax originated from Greek words, which meant "co" or "together," and "sequence, order, and arrangement". Syntax can be defined as the study of rules or patterned relations that determine the way words come together in a sentence (Corbet). It is how different words (nouns, verbs, adjectives) are turned into clauses to make sentences. According to Dr. Wheeler, syntax in Standard English prefers to use a pattern of subject-verb-object and is distingushed from grammar.
Syntax has many theories on formally how it is created and used. But there are two common ideas in all of the theories. First, it creates phrases and second, it creates rules for people to follow. These rules help determine what is acceptable grammactically and what is not. These theories show how syntatic form and sematic meaning relate to one another. Charles W. Morris wrote Foundations of Theories of Signs which shows syntax as a form of a sign and how these signs relate to one another.
Charles W. Morris 
Corbett, Edward P. J. "Classical Rhetoric for the Modern Student." 3rd edition. Oxford: Oxford UP, 1990
Wheeler, Kip L. "Literay Terms." Carson Newman College. 2006 [<http://web.cn.edu/kwheeler>]