Definition of "Chad" :

noun: a family of Afroasiatic tonal languages (mostly two tones) spoken in the regions west and south of Lake Chad in north central Africa

noun: a landlocked desert republic in north-central Africa; was under French control until 1960

noun: a lake in north central Africa; fed by the Shari river

noun: a small piece of paper that is supposed to be removed when a hole is punched in a card or paper tape