Cover Your Own Ass.
Generally used to refer to the legal statements in corporate disclaimers absolving the manufacturer from any guilt if their product should, for example jump up and embed itself in your rectal cavity, then explode.
Wile E. Coyote attempted to bring suit against Acme, Inc. for numerous incidences of personal injury, but their CYOA was too good, and he didn't get so much as an apology
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.