Several adidas Terrex shoes for trail running and hiking are fully waterproof. Others are water-repellent, which means they're made to shed light rain but not to be submerged. For waterproof Terrex shoes, look for GORE-TEX or adidas RAIN.

I also had to work on breaking them in, because they really are a solid pair of shoes. But with the right size (I should add that the online exchange was so easy, thanks adidas), and having worn them for a fair few miles, they are now easily as comfortable as my other textile hikers.

An on-point and waterproof low-rise hiking shoe.

The answer is quite simple: The abbreviation stands for the brand GORE-TEX. This company produces high-quality membranes that make shoes waterproof and breathable. The thin layer of laminate is simply attached to a shoe's inner lining.