What is withdrawnness?

Some articles on withdrawnness:

Schizoid Personality Disorder - Diagnosis - Guntrip Criteria - Withdrawnness
... Withdrawnness means detachment from the outer world, the other side of introversion ... Withdrawnness is a characteristic feature of schizoid pathology, but it is sometimes overt and sometimes covert ... Overt withdrawnness matches the usual description of the schizoid personality, but withdrawnness is just as often a covert, hidden, internal state of the patient ...