- 直系亲属 zhíxìqīnshǔ immediate familylineal relatives or next of kin, typically including parents, children, and spouses
- 直系血亲 zhíxìxuèqìng lineal relativerelatives in a direct line of ascent or descent, including parents, grandparents, children, and grandchildren
- 直系军阀 Zhíxìjūnfá Zhili factionthe Zhili faction of the Northern Warlords
- 直系祖先 zhíxìzǔxiān direct ancestor