The spiritual qi "circulating" "exiting and entering", and "nothing relevant with skin, flesh, tendon and bone" are the clues to understand the original intention of acupoint recorded in Lingshu (Miraculous Pivota). In the paper, regarding the interpretation of these words and phrases in Shuowen Jiezi (Origin of Chinese Characters), in combination with TCM theory, the connotations of acupoint are summarized in 4 aspects, including the essential characteristics of the changes in the antipathogenic qi, functional property of pathway communication, the clinical features of diagnosis and treatment and the three-dimensional structural characteristics. It is enlightened that the antipathogenic qi and its changes are the most essential rather than the anatomic structure of acupoint. The application of acupuncture and moxibustion acts on qi activity of acupoint rather than flesh and joint. All of those mentioned above indicate the essential issues on the clinical therapeutic effects of acupuncture and moxibustion, which are significant and valuable nowadays in clinical practice.