Leaf edges are useful for identifying trees. When you can describe the edge on a leaf, you may already know what kind of tree it belongs to. But leaf edges are useful for more than just identifying trees. They are also useful for learning Latin.
There are four types of leaf edges. You can see some really good pictures of these types at Virginia Tech’s dendrology website.  Below, I have created a list of words we use to describe leaf edges, and I also explain the etymology.
Smooth (or “entire”)
Okay, the word smooth does not come from Latin. But we also use the word entire to describe these edges. As in, the entire edge is smooth. The word entire comes from the Latin word integer; which, in its accusative case, takes the form integrum. The Latin word integer means complete, whole, or intact. Which is why we call the whole numbers integers.
We describe leaves that have large teeth as being dentate. The word dentate comes from the Latin word dentatus, which means full of teeth. The Latin word itself derives from a simpler noun, dens, which means teeth. American chestnut leaves are dentate.
Just as a knife can be serrated, a leaf can be serrate. These two words have the same etymology, and it’s hard to say when we should use serrate instead of serrated. I think the gist of it is that serrate is more common in scientific communities, whereas serrated is more common in every day speech. The two words descend from the Latin word serratus, which means saw-shaped. The word serratus is the past participle of the verb serro, which means to saw. As you can see from Virginia Tech’s website, red maple leaves are serrate.
Lobes and Sinuses
The last category are the leaves that have lobes and sinuses. The word lobe comes from the Ancient Greek word lobos, which means any projection or division, especially those that have a round shape.  The word was appropriated much later into the Latin language (sometime after the 14th century CE) and latinized as lobus. The word sinus, on the other hand, seems to have a more straightforward descent from Latin. The word is the same in both languages. The word sinus is a noun meaning any hollow or cavity. White oak leaves are lobed, and by looking at them you can clearly see the pattern of lobes and sinuses.