What is "run-on sentence"

n. (context grammar English) an ungrammatical sentence in which two independent clauses that should be joined by either a semicolon or a comma and coordinating conjunction or should be separate sentences are written as a single sentence, the clauses often being separated only by a comma.

n. an ungrammatical sentence in which two or more independent clauses are conjoined without a conjunction

A run-on is a sentence in which two or more independent clauses (i.e. complete sentences) are joined without an appropriate punctuation or conjunction. For example:

Although this is generally considered a stylistic error, it is occasionally used in literature and may be used as a rhetorical device.