Any of a group of antidepressant drugs, such as amitryptyline, that contain three fused benzene rings and that block the reuptake of the neurotransmitters norepinephrine and serotonin in the central nervous system.三环抗抑郁药：含三个熔苯环的抗抑郁药类，如阿密曲替林，抑制中枢神经系统中神经传递素去甲肾上腺素和5-羟色胺的再吸收