The best way to do a rewrite may be incremental, but the terminology of "full rewrite" doesn't usually refer to an incremental rewrite, it refers to starting from scratch.
I don't think that's true -- a "full" rewrite is used in contrast to a "partial" rewrite, where only part of the system is replaced. It's called a "full" rewrite because the goal from the start is to fully replace the system with new code.
Consider that if this were not true, then there would be no way to describe an incremental full rewrite, nor any way to describe a from-scratch replacement of a subsystem.
The best way to do a full rewrite is incrementally, with test support and consideration for natural separation of internal subsystems.