I've recently become confused at the use of the word express, specifically in circumstances where companies use the word to describe a slightly different service than their typical service.
For example the USPS has Global Express Mail, which offers to move a package as quickly as possible (for added fee, of course). Similarly, some train services called "express" are/were offered as or advertised as faster services (probably a callback to the Pony Express). Also common is the "express lane" that gives you faster service in any sort of queued waiting scheme.
Conversely, sometimes companies have used the word express to denote free or cheap, and even sometimes diminished. Software companies do this frequently, calling versions of their software that are cheaper and sometimes containing less features "express versions".
I'm most recently confused by Uber's new service "Express Pool", an extension of "Pool". In Uber Pool, the driver picks up you and others near you, then drops all passengers off near the same location. It takes a bit longer than regular Uber, but costs less. Pool Express extends the savings further by asking all the passengers to walk and wait a bit and meet in the same spot, so the driver only has one pickup.
So here we have Uber, a transportation service, using the word "express" for a service that's actually slower.
Looking in a few dictionaries, I found entries that define it as "fast", but found none that define it as "cheap". But there's plenty of examples of people using it as "cheap". I'm hoping an answer can clarify this usage difference, and possibly note how the word came to have these two meanings, which, at least in Uber's case, can imply the exact opposite meaning (i.e. if Uber Express Pool becomes popular, people may come to think the word means slower).