"Coils Splitting", a design reserved for humbucking pickups with two magnets and two coils. When "cutting a single" (which can be accomplished in a variety of ways, including gear dials, push/pull knobs, gear keys, etc.), the two coils are disconnected, leaving only one coil working. In other words, "cut single" turns the humbucker into a single coil pickup. This is a very useful feature that allows the musician to get a single-coil tone in a humbucker without having to replace the guitar. Of course, you must also know that the original noise removal feature disappears when you cut the single.
This simply means that the humbucker can be converted to work as a single pickup by the function of cutting the single, giving it the tone style of a single pickup. The advantage of this is that it gives the guitar more variety, usually using humbuckers for a brighter, punchier tone, and single coils for a softer, fuller tone."