[aclimatt]

Indeed. This website has been pushing this word for almost 10 years (since 2012, along with others, but sonder seems to be their biggest "hit"), seemingly just for the sake of coining a neologism.

But I too have never actually seen it used in the wild as a word, and now it's become a short-term rental startup (https://www.sonder.com/) and a support network (https://www.sondersafe.com/) -- though the second actually does seem to relate to the word. The first probably just used it because it sounds like slumber + wander or something.

The goal of the website is to coin words for specific emotions. Maybe they should focus on writing content that requires them and get that published first. Demonstrating a need and all that...