"wonky hole" means: A type of undersea hole or spring on the Great Barrier Reef in Australia, out of which emanates fresh water that has flowed underground from.... This is a fairly neutral word with no inherent risk attached. There is no real cause for parental concern; it is descriptive vocabulary rather than something dangerous. If your child uses it, context will usually make the meaning clear. A brief, curious question about where they heard it is generally enough to know whether to follow up.