Cannabinoid receptor 1: One of the two known receptors in the endocannabinoid (EC) system associated with the intake of food and tobacco dependency. Blocking the cannabinoid receptor 1 (CNR1) may reduce dependence on tobacco and the craving for food. The gene encoding CNR1 is located in chromosome region 6q14-q15. Also called the CB1 receptor or CB1. So far, drugs that block this receptor have not been shown to be beneficial for smoking cessation.