Disordered eating is a symptom of an eating disorder.
Eating disorders are clinically identified issues that fit a pre-existing set of medical criteria (although this is very broad as they look different on everyone).
Disordered eating describes a variety of abnormal eating behaviors that, by themselves, do not warrant diagnosis of an eating disorder. Not severe “enough” to be considered an eating disorder, but still can be challenging to deal with in their own right.
So no the terms are not used interchangeably, but there are definitely links there. Disordered eating can quickly progress into an eating disorder.