part of longissimus longissimus cervicis A slender muscle medial to the longissimus thoracis that arises by long thin tendons from the transverse processes of the upper four or five thoracic vertebrae, is inserted by similar tendons into the transverse processes of the second to sixth cervical vertebrae, and extends the spinal column and bends it to one side. BTO:0001650 BrendaTissueOBO musculus longissimus cervicis