Ocean baby
A baby that’s half fish and half insult. It’s what you call ocean animals when you’re too lazy to think of a real name and just want to make fun of them.
That octopus is an ocean baby. It has eight arms and a face that says 'I hate you.'
My parrot is an ocean baby. It squawks like it just got yelled at by a crab.
That shark is an ocean baby. It probably bit your lunch and then cried.