Monster: A creature whose identity is created (or distorted) by the imagination or legend.
The behavior of gang members is like a legend based on distant stories that becomes real to the people working in the prison system. Monster seems to be an apt name for the author because, as a gang member, he is treated as something dangerous and inhuman. The officers retaliate disproportionately to his disobedient acts because they are afraid of something vague and intangible. According to Monster, their fear extends beyond gang members to young black men in general.
Illegitimate: Something that is not accepted by the mainstream or does not fit into the usual processes of a culture.
Monster is not accepted by his “father” because he is illegitimate. Although he grows up with Scott, Scott is unwilling to accept him as his child because it culturally unacceptable to embrace a child that was born of an affair. Later he finds it easier to adapt to an illegitimate living and join a gang than to be successful the legitimate way. Because he is poor, it would be difficult for him to get the college education which would enable him to get a good job. The book suggests that white people, who comprise the majority of society, are afraid of young black men and gang members. If this is true, it becomes nearly impossible for him to make a legal living once he becomes involved in a gang and goes to jail.
Misrule: Governance that comes to resemble anarchy because it is misguided.
All the groups of Crips follow strict rules, but they lead to civil war among the Crips. In jail, the different groups of Crips are still fighting even though there are few of them and they have other enemies that want to kill them. Even among the Crips that want to unite, the leadership is conflicted and Monster realizes that it is flawed and self-destructive.