What’s a stick insect? Easy - an insect that looks like a stick. What’s a tiger moth? Same deal - a moth that looks like a tiger.
Both these insects have names which are compound nouns. The second noun insect/moth in some way resembles the first, i.e. a stick/tiger. Rhinoceros beetle is another example.
A picture of Carausius Morosus also known as the common stick insect. Photograph by Evanherk, distributed under a CC BY-SA 3.0 license.
Obviously not all insects are named accordingly. Fruit flies don’t look like fruit and fire ants don’t come in tiny flaming swarms (thankfully).
But for those which are, using the structure ‘Noun X describes the appearance of Noun Y,’ opens the door for a whole bunch of silliness. To demonstrate, a stick insect is an insect that looks like a stick. It’s also an insect that looks like a stick insect. Furthermore, it’s an insect that looks like an insect that looks like a stick insect. You get the idea.
A picture of Carausius Morosus Recursus also known as the common stick insect insect.
In other words, the names of these insects can be infinitely recursive.
Of course, this isn’t restricted to insects names either. You can do it with any compound noun formed in the same way.
So, if you’re ever out on the ocean and fall off your banana boat boat, you better hope you end up next to a barrel sponge sponge sponge and not a hammerhead shark shark shark shark.