Dragons, though, are ill-defined. What a dragon is can be different depending on what time and in what culture you ask the question. Early Jewish apocalypse tales featured Behemoth and Leviathan, monstrous beings of primordial chaos like Tiamat that opposed YHWH and could have very well been called draconic. The Greek drakon (one who looks/stares) was a large, serpent-like creature that guarded different things, like the Drakon Ismenios, which guarded a sacred spring of Ares near Thebes. This idea of a dragon was later subsumed into Old English culture, where dragons (draca), described as wyrms or serpents, hoarded treasure and would fight heroes to defend it, like is seen in the dragon that slew Beowulf with its venomous bite. But if you look further east, dragons were water spirits in most of East and Southeast Asian myth, and were highly intelligent, shapeshifting, snake-like beings that controlled the rain.
The wide reach of D&D on the modern fantasy landscape has led to other Tiamat depictions, some close to this reimagining, others departing to make her a breasty anime girl who can shoot lasers out of her hands. But each version clings very closely to the idea that the original Tiamat was a dragon like we think of them in the West today, wings and all. It’s my belief that even if Tiamat was the mother of the modern-day dragon, she and her original depictions should not be forgotten. She should be remembered in all her snakey, weird metaphorical glory, vague descriptions and all.
Thanks for reading!
Also, here's an aside to talk about Satan for a sec:
If Europeans took the ideas of big snakes and turned them into dragons, and Satan’s first appearance in the Bible was as the serpent that tricked Adam and Eve into consuming the fruit from the tree of knowledge of good and evil, why hasn’t Satan taken the form of a dragon in the wider Christian mythos today? Sure the Middle Ages had depictions of him as a draconic-ish creature at times, but I want a Game of Thrones style dragon Satan to have his own story. Give me the Paradise Lost cultural fanfic that canonizes Dragon Satan. I’ll be waiting.
Sources
https://en.wikipedia.org/wiki/Tiamat
https://forgottenrealms.fandom.com/wiki/Tiamat
https://en.wikipedia.org/wiki/European_dragon#:~:text=MS%20Harley%203244%2C%20a%20medieval,a%20fully%20modern%2C%20western%20dragon.
https://www.theoi.com/Ther/DrakonIsmenios.html#:~:text=THE%20DRAKON%20ISMENIOS%20(Ismenian%20dragon,monster%20with%20a%20heavy%20stone.
https://en.wikipedia.org/wiki/The_dragon_(Beowulf)#:~:text=The%20Beowulf%20dragon%20is%20described,vengeful%2C%20fire%2Dbreathing%20creature.
https://www.youtube.com/watch?v=3eXAPwjASEQ
http://oracc.museum.upenn.edu/amgg/listofdeities/tiamat/index.html#:~:text=Tiamat%20is%20a%20personification%20of,in%20the%20En%C5%ABma%20Eli%C5%A1%20TT%20.
Enuma Elish
https://www.ancient-origins.net/myths-legends-asia/tiamat-mesopotamia-0010565