Definition of "split infinitive" [split infinitive]
An infinitive verb form with an element, usually an adverb, interposed between to and the verb form, as in to boldly go.(noun)
American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.