For all Stack Exchange sites - Is there a technical limitation to encouraging users to freely create tags, if there is sufficient moderation - and if they are not being misused for "IM" purposes, etc.?

Are there any notable usability issues?

Example: book-heraclitus, philosopher-heraclitus, philosopohy-heraclitus, etc.

Stack Overflow, Tag Folksonomy and Tag Synonyms - It’s important that questions get tagged correctly, because that makes it easier for everyone to find the questions they’re interested in — and potentially answer them.

Can tags and tag-synonyms within the Stack Exchange community be created freely, (be very specific, and even prolific, similarly to how "Hashtags" are used in other sites), as long as they are managed and eventually merged when needed, (as synonyms)?

Is it better to err on the side of many tags and tag-synonyms, (and merged later)? Or, is it better to err on the side of conservation?

A recent comment on a Stack Exchange site stated:

The point of my tag edit is that [a certain tag] is not "a thing" -- adding that tag just pollutes the tag pool. Tags in the SE system are not like hashtags to draw attention to things. They help to classify Q&As, and for a classification system to work, there must be real "categories" represented by the tag. So please don't proliferate tags. Thanks!

  • 1
    I don't see any use in this. Jun 30, 2017 at 21:40
  • 2
    Can you give an example of what you're talking about? If you're commenting or talking about a tag in a post, there's markup for that... tagging ([tag:tagging]) in comments, posts, or chat will create a link to that tag on the site you're on (if it exists) and in a per-site meta, it will link to the main site instance of the tag.
    – Catija StaffMod
    Jun 30, 2017 at 21:42
  • @Catija - I added an example as requested, though I am afraid this is still being misunderstood. Again, the question is merely, "is it okay to encourage users to err on the side of over-kill, (for searchability), or are there certain technical limitations that should be kept in mind? What is the reasonable limit to tag-synonyms?" .... Feel free to suggest an edit. Jun 30, 2017 at 21:51
  • I'm not sure how you propose to have all of these tags on one question. Each question is allowed only five tags maximum.
    – Catija StaffMod
    Jun 30, 2017 at 21:53

1 Answer 1


I see no benefit to your tag examples. They are compound tags, which are generally not accepted.

The way the autocomplete works for tags, if someone has a question about Heraclitus, all three of those tags (if they existed) would populate in the tag recommendation box by simply typing "heraclitus" (or even a shorter form of it like "hera"). As such, no benefit is gained by having all three.

Further, it is damaging to the search function.

If someone is interested in questions about Heraclitus, there is the potential that only one of the tags appears on a question, meaning that the searcher now has to view all tags containing Heraclitus rather than only one. It's much simpler to allow only the single tag and expect that all questions on the subject include that tag.

Note that there is also what we call a "meta" tag. The tag on the Philosophy site, for example, is such a tag. There's no reason to tag something on that site as Philosophy as every tag on the site would have it.

As for technical concerns, there are a couple.

Questions may only have five tags maximum. This means that having dozens of potential tags for the same topic clutters up the tagging and makes it impossible to prioritize which tag to use. Fewer tags to choose from negates this issue and is the preferred option.

Tags that are not used on more than two questions and have no tag wiki or excerpt will be automatically deleted by the system after a certain amount of time. So if you create a tag and it's not used elsewhere, you'll end up with it disappearing after a month or so.

In relation to synonyms, I think you're overthinking how they're used here.

Synonyms are designed to be used when two words (often in versions of English) are both used for the same thing. Look at the existing synonyms list on any site you're a fan of... here's the one on Cooking. You'll see that all of the synonyms are either versions of the same thing (sweet-potatoes vs sweet-potato, flavor vs flavour, children vs kids) or are simplifications of tags (history instead of food history because "food" is implied).

Occasionally, a subject is too small for its own tag, so we combine tags into one. On cooking, an example is the tag. Because someone might type "black" or "white" in before "pepper", we have the tags and as synonyms of the generic tag. This is different than your examples. "Black pepper" and "white pepper" are actual ingredients. They are a thing, we as a site went through a meta discussion and decided to use one tag for this instead of three.

You'll notice, however, that the tags on the synonyms list aren't what I'd consider a "compound tag". A couple of them have unnecessary "food" or "cooking" terms that were stripped out for the master tag but most of them are literal synonyms, pluralizations, or tense changes on verbs. I don't think any of these are examples that equate to the examples you came up with in your question title.

  • Tags and tag synonyms are generally reserved for tags that people have actually used. We don't proactively create tags on the off chance that someone will use them. That's never been how SE tagging works. So, as an example, if no one has asked a question about a specific film on Movies & TV we don't create the tag so that it already exists should someone want to ask about it in the future. Any tag that's not used on any questions is deleted after about 24 hours. There's also no mechanic to create tags unless they're used on a question - for that reason.
    – Catija StaffMod
    Jun 30, 2017 at 23:17
  • What added benefit is there to have dozens of tag synonyms? What would be the master tag? No one is going to try to use book-heraclitus if the tag heraclitus exists. Synonyms are never used on actual questions. If someone attempts to use book-heraclitus and it's a synonym of heraclitus, all anyone sees is the latter... for all intents and purposes, the tag doesn't exist.
    – Catija StaffMod
    Jun 30, 2017 at 23:49
  • Catija - Another example: "Aristotle" and "Aristotle-Philosophy", but for people examining Aristotle's Works, there might be a tag-synonym between Aristotle-Philosophy, Aristotle-Histories, and Aristotle-Writings." Either way, I can see your point regarding the use-case you cited, where: a lot of very closely related tags would cause significant usability issues, where people wouldn't be able to determine which tag to use. This is more than sufficient as a basis for a proposal in another community for managing tags. Thank you very much! And accepted. Jul 1, 2017 at 0:06

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .