This neologism refers to the effect of incarceration on long-term psychology.  In my capacity as college English teacher in a medium-security prison in the Midwest, I witnessed prisonization in two ways:  first, the first-time property offenders showed fear of associating with the “other”—the violent offenders, the sex criminals, the weight-lifters, etc., not only in the general population but in the classroom.  Second, the content of their essays reflected a defensiveness, a reserve of personal information, and I found I was unable to let fellow-students share their papers with each other.  When asked why, they said that prison society did not allow vulnerability of any kind.  Also, to be eligible for the class, the students had to be eligible for release or parole within two years, and this brought with it an anxiety which I recognize as part of prisonization, especially with their reserve with the guards.