Definition of "Chapter" :
noun: a subdivision of a written work; usually numbered and titled
"He read a chapter every night before falling asleep."
noun: a series of related events forming an episode
"A chapter of disasters."
noun: a local branch of some fraternity or association
"He joined the Atlanta chapter."
noun: an ecclesiastical assembly of the monks in a monastery or even of the canons of a church
noun: any distinct period in history or in a person's life
"The industrial revolution opened a new chapter in British history."