The key word in the names "Zhuyin" and "Zhulong" is 燭, pronounced zhú in present-day Mandarin.

In the name Zhulong, the zhú modifies the noun 龍 (lóng) and thus intends a "shining", "torch-like", or "torch-bearing" Chinese dragon.

In the name Zhuyin, the zhú sits beside the noun 陰 (yīn), which describes both regular darkness and the feminine principle of the yin-yang, with an implicit conjunction between them.

According to present reconstructions, these variant characters 逴 (now chuò) and 趠 (now zhuó) sounded closer to the pronunciation of 燭 in old Chinese, although not homophonous.

[2]Guo Pu (276-324 CE)'s commentary on this passage is: 'Enlightener' is a dragon; he enlightens the nine yin (darknesses, i.e. the nine points of the compass at the opposite, dark side of the earth, which is a flat disk; these nine points are North, South, East, West, North-east, North-west, South-east, South-west, and the Centre)".

[1] Guo Pu quotes a legend from a no longer extant Classic of Poetry commentary[6] that "the sky is insufficient to cover the northwest, so there is no ebb and flow of yang and yin.

"[10] The Huainanzi (2nd century BCE) has a section called the "Treatise on Topography" (4) that refers to Zhulong: The Torch Dragon dwells north of Wild Goose Gate.

200 CE) composed a commentary on the Huainanzi that explains[12] "Weiyu is the name of a mountain ... in the shade of the northern limit, the sun cannot be seen."

The Records of Penetration into the Mysteries (洞冥記, Dòngmíngjì) describes ritual activities of Emperor Wu of Han (r. 141–87 BCE).

Although this text does not mention Zhuyin or Zhulong by name, Wu's Taoist advisor Dongfang Shuo describes a mythical northern "Azure Dragon" which bears a torch: ... in the year 99 before our era the emperor Wu convoked a meeting of magicians and learned men, at which Tung Fang-soh spoke as follows: "I made a journey to the north pole, and came to a mountain planted with fire, which neither the sun, nor the moon ever illumines, but which is lighted to its uttermost bounds by a blue dragon by means of a torch which it holds in its jaws.

I found in that mountain gardens, fields, and parks with ponds, all studded with strange trees and curious plants, and with shrubs which had luminiferous stalks, seeming at night to be lamps of gold.

Major describes the Torch Dragon as "well-known in early Chinese mythology" and suggests it is probably "a mythical interpretation of the aurora borealis".