The "SUB" is an unusual species of bird that grows inside sea urchins, acting as if the sea urchin is the womb and the bird a fetus. When the sea urchin dies, impregnated with the bird, it crawls out. The Sea Urchin bird is both a myth and a fact. Whether you believe it is in existence or not, it has not been proven wrong therefore cannot be classified as "extinct." it is most commonly seen when students dissect sea-urchins in Marine biology labs, the bird flies out of the urchin as the student cuts through the exoskeleton.
Holy shit Karen! Did you just see that SUB fly out of that Sea urchin?!?!

-or when used in sarcastic remarks

"what do you have a sea-urchin bird up your ass?"

"whats he got up HIS ass? A sea-urchin bird?"
by ProfessorKnell December 20, 2007
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A nickname for your most sane, but slightly insane, friend. They are grounded and hard working, but are also there to have a good time. They are open to talk at anytime, day or night, and are excellent conversationalists. They can be very matter of fact, and will be honest with you always. They are a “4 lifer”, and are always there when you need them. They are great for movie nights, mall meetups, and annoying with your obsession with Tom Holland. They are forever an icon, and are going places in life. They are also always extremely horny.
“Hey my MAGESTIC SEA BIRD, did you see Tom Holland in that new movie trailer?”
“Yeah, he makes me so horny.”
“NO, he is MY MAN.”
by TomHollandsPissPig May 29, 2021
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