In reference to a code:
In reference to a code (such as the United States Code), the word title refers to the broad subject heading under which a law is classified. For example, the United States Code is organized into fifty titles, each title pertaining to a particular subject. 18 U.S.C. § 925A (2000) (a provision added to the U.S. Code as part of the Brady Act) is the citation for section 925A of Title 18 (Crimes and Criminal Procedure).
In reference to an act:
In reference to an act, (such as Title VII of the Civil Rights Act), the word title refers to a large portion or subset of the act. For example, Title VII of the Civil Rights Act is codified in Title 42 of the United States Code. But here, Title VII refers to a portion of the public law that appears below the Roman numeral seven in the Act's original Statutes at Large version.
--from the Harvard Law School Library One-L dictionary