People who wander around aimlessly and always seem to get in your way in stores and supermarkets, chatting on their cell phones and paying no attention to their surroundings.

A phrase to describe someone who is cognitively degenerating. Synonym of "going off the deep end". Can have varying degrees of severity.

Reference to the song "Hey You" by Pink Floyd. The line "and the worms ate into his brain" makes no sense in an otherwise linear and literal narration throughout the lyrics.

A person with nowhere to go and nothing to do who wanders the sidewalks aimlessly in a swervy, slow path that blocks the paths of people who do have somewhere to go and something to do.

One who has difficulty determining their next course of action in traffic (sometimes going 10-20mph top speed), and, as a result, is not predictable and does not use their turn signal.

1. n.: In tourism industry, those ones aka tourist, specially the one in hords going up and down as a pack, inside and outside shuttle buses and meanders other tourist atractions. Each one in a shoal of visitors wandering through the city center. Not always nor exclusively applied in a pejorative manner.

One who wanders about thoughtlessly.

An old person who walks at an extremely slow pace. (This word is a combination of "meander" which means to walk slowly with no apparent destination, and "neanderthal" which refers to something old, ancient or prehistoric.)