- 赤道几内亚 chìdàojǐnèiyà Equatorial GuineaA country in west-central Africa.
- 赤道面 chìdàomiàn equatorial planethe plane passing through the center of a celestial body (such as Earth) that is perpendicular to its axis of rotation
- 赤道仪 chìdàoyí equatorial mountan astronomical telescope mount used to compensate for the earth's rotation by moving in line with the celestial equator
- 赤道逆流 chìdàonìliú equatorial countercurrentan eastward-flowing ocean current found near the equator in the Pacific, Atlantic, and Indian Oceans
- 赤道雨林 chìdàoyǔlín equatorial rain forestRainforest located in the equatorial region, characterized by dense vegetation, high biodiversity, and tall trees; it is often considered one of the most difficult regions on Earth to develop.
- 赤道几内亚共和国 chìdàojǐnèiyàgònghéguó Republic of Equatorial Guineaofficial name of Equatorial Guinea, a country in Central Africa
- 天球赤道 tiānqiúchìdào celestial equatorThe imaginary circle where the plane of the Earth's equator intersects the celestial sphere.
- 反赤道流 fǎnchìdàoliú equatorial countercurrentequatorial countercurrent; an ocean current that flows eastward against the general westward flow of the equatorial currents
- 赤道无风带 chìdàowúfēngdài doldrumsequatorial calm belt; a region of the ocean near the equator characterized by calm winds and sudden storms