/ Dictionary / Index C carotid sinus: Meaning and Definition of Find definitions for: carot'id si"nus Pronunciation: [key] — Anat. Anat. specialized nerve end organs producing a slight dilatation of the carotid artery where it branches into the external and internal carotid arteries, responding to changes in blood pressure by mediating changes in the heartbeat rate. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. carotid body carotin Related Content Daily Word Quiz: lunar Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language