a main division of a book, treatise, or the like, usually bearing a number or title.

a branch, usually restricted to a given locality, of a society, organization, fraternity, etc.

the Connecticut chapter of the American Red Cross.

an important portion or division of anything

The atomic bomb opened a new chapter in history.

Ecclesiastical .

an assembly of the monks in a monastery, of those in a province, or of the entire order.

a general assembly of the canons of a church.

a meeting of the elected representatives of the provinces or houses of a religious community.

the body of such canons or representatives collectively.

any general assembly.

Liturgy . a short scriptural quotation read at various parts of the office, as after the last psalm in the service of lauds, prime, tierce, etc.

Horology . any of the marks or numerals designating the hours on a dial.

to divide into or arrange in chapters.

noun

affiliate , branch , clause , division , episode , member , offshoot , part , period , phase , stage , topic , unit , wing , assembly , body , capitulary , clan , contingent , era , lodge , meeting , organization , post , section