It seems that in the US there is no standardized abbreviations for cities/towns, only for states. There are a couple of abbreviation types that are in unofficial use –3 letter Airport codes, USPS 2 letter codes and Associated Press style codes for cities/towns.
Some places in US in OSM have these abbreviations, but it seems there is no OSM community consensus on which unofficial abbreviations could be used for short_name tag purposes.
There are even some additional lists for some states, from departments of transportation or some municipalities, but these, although mention some abbreviation, do not clearly reference whether these represent codes that should be used in general or were these made for some specific list/statistics/ counting.
Currently there is no clear source that can be used for adding town abbreviations to OSM.
Still, it seems that these unofficial abbreviations are commonly used and are important for search purposes, as well as some specific local names of cities/towns, such as “The Big Apple” for New York, “Windy City” for Chicago etc.
I want to ask you for your opinion on how to process these types of unofficial names. Should unofficial short_name tags should be added, and what about “nicknames” like “The Big Apple”?
The three-letter FAA LID is the primary official identifier of an airport, and the two-letter USPS abbreviation is the primary official identifier of a state. We put them in ref=* or similar keys rather than short_name=*. These identifiers are certainly shorter than the full names, but the rules for deriving these codes from the full name are different and more rigid than the traditional rules for forming conventional abbreviations in English.
Some city abbreviations like “NYC” and “L.A.” are extremely common. The USPS will probably deliver a letter addressed to “NO, LA”, though only if you correctly indicate the ZIP code. There’s no standard for this sort of abbreviation, but you might find some in maps and gazetteers. short_name=* is appropriate for these abbreviations.
Historically, many more cities had abbreviations and contractions. Some like “Col’s” have completely faded away, while others like “Cinti.” are still occasionally used by older folks. I only ever see these abbreviations in phone books and on space-constrained signs, such as signs for “Cinti–Cols Rd”. I suppose they can go in short_name=* too, to the extent that they’re still in use.
Probably every style guide discourages abbreviating city names in lists and running prose. The state abbreviations only exist because of the practice of qualifying a city by the state. For example, AP style would recommend “Kansas City, Mo.”, not “Kan. City, Mo.”
Cities have lots of nicknames that are used in various contexts. We should keep them separate from more practical names. For example, Cincinnati’s nicknames include “Cincy” and “The Queen City”. “Cincy” is quite informal, but locals often say it unironically as a replacement for the formal name, so it should go in alt_name=*.
There’s apparently a nickname=* key for something like “The Queen City”. I’m unsure if any geocoder actually uses it, since few users would ever enter one of these nicknames into a search bar. One alternative use case is named entity recognition in news reports. Journalists often refer to cities by their nicknames to punch up a headline or avoid repetition within an article. Tagging nicknames could make it easier for a natural language processing system to detect these oblique references, though Wikidata might already have better coverage.
Incredibly, the only US place=city with a tagged nickname is Manchester, NH, a.k.a. Manch Vegas (?!?!).
Many “nicknames” like The Big Apple, Philly, etc. are currently tagged as loc_name, but some like Cincy are in alt_name. alt_name seems more often used for a modification of the name that’s roughly equally valid, e.g. New York City for New York, Washington DC for Washington.
Meanwhile a lot of shortenings, whether they’re airport codes that the city has taken on like ABQ or initialisms like SF or NYC, end up in short_name.
I agree that these are by their nature not formalized, unlike the state abbreviations and airport codes you mention above. So there necessarily won’t be a clear source other than local knowledge. I also wouldn’t personally spend much brain power on exactly which *_name tag each nickname ends up in: if it’s in the data using one of the common tags, a geocoder can pick it up (i.e. searching “Big Apple” in Nominatim does pull up New York).
Yeah, people call it that. Don’t ask me why, I don’t know more than the poorly-cited Wikipedia paragraph. The morning talk radio hosts and the newspaper columnists and the Reddit/Facebook commenters all use it, which usually confuses any newcomers.
I decided to use the uncommon tag partially because I was curious about data consumer adoption and decided testing it was more fun than searching through code. Unfortunately, I didn’t find anything that supports it.