A creative insult first coined in the song "Let me borrow that top" by kelly, generally used in a joking manner to break up the monotonous "Fuck you! No fuck you!" line of trash talking
Someone or something that bites your ankles.
To a postman, an ankle biter is often known as a dog.
To an adult, an ankle biter may be a toddler.
To hikers, an ankle biter is sometimes a tick.
And so on.