2 of my therapists used it interchangeably with Exposure Therapy.
1 said they’re the exact same thing, just use different words to describe the process, with one more masculine/direct and the other more feminine/feely/wordsy.
The other T believes they actually are different therapies, on the same continuum; both ends reaching for the middle. One working outside in, the other inside out; one working head to heart, the other working heart to head.
The both believed that some clients can do either, but most have a fairly strong preference in one direction or the other.