Malingering is best described as type of dissimulation. Dissimulation is a general term that is used to describe a person who is deliberately distorting or misrepresenting psychological symptoms in the context of an evaluation.  There are several different types of response styles that fall under the general dissimulation including malingering, defensiveness, irrelevant responding, and random responding.

The key issue is that all of these styles presume an attempt to distort the results of an evaluation, but  malingering is a term typically reserved for those cases in which one  is believed to be  intentionally trying to fabricate or exaggerate psychological symptoms. In contrast,  defensiveness is a style of responding that attempts to minimize any psychological symptoms. Irrelevant responding and random responding are just what they sound like, response styles that are likely to reflect a disengagement from the active participation in an assessment , and more likely to reflect a general oppositional approach to  the evaluation  as opposed either  exaggerating or minimizing symptoms.  Also note that random responding and irrelevant responding are also seen in genuine conditions  in which the person is so impaired as to be unable to meaningfully participate in  the assessment.

It should be obvious that Malingering is a term with very significant implications within legal proceedings and should be used with great caution by mental health professionals.  It presumes a motivation to deceive and manipulate the system for some type of  personal gain. Unfortunately, it is all too common that mental health professionals  in many different settings will make reference to a person "malingering" in the absence of clearly explaining the underlying evidence supporting such a statement.