In common usage, the "permanent" and "persistent" definitions are sometimes conflated and used interchangeably. However, the acronym "PVS" is intended to define a "persistent vegetative state", without necessarily the connotations of permanence, and is used as such throughout this article. Bryan Jennett, who originally coined the term "persistent vegetative state", has now recommended using the UK division between continuous and permanent in his book "The Vegetative State", arguing that "the 'persistent' component of this term ... may seem to suggest irreversibility".