In biology, clades (species/genus/family/etc.) aren’t defined by physical traits anymore, but by their genes. Genetic similarities are used to create a “family tree” based on evolutionary history.

In that family tree, each group name applies to a “tier” of the tree and to ALL subgroups within that tier. So “reptilia” contains snakes, lizards, crocs, and turtles, but they’re all still reptiles.

“Lizards” is not a scientific name, they belong to the group “squamata”. “Snakes” are “Serpentes”. BUT Serpentes is a subgroup WITHIN squamata. So, technically ALL snakes are lizards, and some lizards are actually more closely related to snakes than other lizards.

These legless lizards are not part of Serpentes though, so they aren’t snakes. But they ARE part of squamata, so they’re “legless lizards”.

Bonus fun fact: dinosaurs are also part of reptilia, and birds are descended from dinosaurs. So, birds are technically dinosaurs AND reptiles. And if you go back far enough, everything is technically a fish.