a measuring instrument that sends out an acoustic pulse in water and measures distances in terms of the time for the echo of the pulse to return; "sonar is an acronym for sound navigation ranging"; "asdic is an acronym for antisubmarine detection investigation committee"
having a bearing on or connection with the subject at issue; "the scientist corresponds with colleagues in order to learn about matters relevant to her own research"
occurring or encountered or experienced or observed frequently or in accordance with regular practice or procedure; "grew the usual vegetables"; "the usual summer heat"; "came at the usual time"; "the child's usual bedtime"
a subdivision of a written work; usually numbered and titled; "he read a chapter every night before falling asleep"
a series of related events forming an episode; "a chapter of disasters"
a local branch of some fraternity or association; "he joined the Atlanta chapter"
an ecclesiastical assembly of the monks in a monastery or even of the canons of a church
any distinct period in history or in a person's life; "the industrial revolution opened a new chapter in British history"; "the divorce was an ugly chapter in their relationship"