Cervicogenic headache is referred pain (pain perceived as occurring in a part of the body other than its true source) perceived in the head from a source in the neck. Cervicogenic headache is a secondary headache, which means that it is caused by another illness or physical issue. In the case of cervicogenic headache, the cause is a disorder of the cervical spine and its component bone, disc and/or soft tissue elements.

Reference: by  Bogduk N, Govind J. https://americanmigrainefoundation.org/resource-library/cervicogenic-headache/ , july 1st,2019