From time to time, I see comments on questions that prompt the question asker to define terms that 

* Are not defined in the question
* Are not well known to 100% of people, especially outside specific area of concentration (e.g. political terms local to Indian politics in 2016)
* However, are **well defined terms**
* And, moreover, fairly easy to figure out what they mean even for a non-expert.

**Example Q (1 upvote only):**

> 
> **Q: ["Modi's Demonetization move?"](https://politics.stackexchange.com/questions/13523/modis-demonetization-move)  
> 
>  What is the real advantage of Demonetization if it does not solve the problem of black money in India?** [india](https://politics.stackexchange.com/questions/tagged/india "show questions tagged 'india'")
> 
> 
> 

**Comment (with 3 upvotes):**

> 
> *Please define your terms: Demonetizing, black money and how it relates to higher denomination notes*
> 
> 
> 

**However:**

* What "demonetization" means is clear [from a basic Google search](https://www.google.com/#safe=off&q=demonetization+india+modi), including [Wikipedia page](https://en.wikipedia.org/wiki/Indian_500_and_1000_rupee_note_demonetisation) that's in first 10 results.
* What "black money" means is equally clear [from a basic Google search](https://www.google.com/#safe=off&q=%22black+money%22+india+modi), including [Wikipedia page](https://en.wikipedia.org/wiki/Indian_black_money) that's in the first 5 results.

Both searcher return easily read articles explaining the subject area.

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There seems to be a balance that is needed to achieve here between two competing goals:

* **Goal 1**: Attract as wide user base as possible, by making every question potentially easily readable by every user, no matter how lay-person and uninformed.
* **Goal 2**: Attract experts. And presumably, someone who is an expert would either already know those terms (this is kind of an important topic in world politics), or possess enough skills and expertise to learn about them as I just illustrated.

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This seems to me to be the content equivalent of asking "can you please define what a lambda is" in a question about Java 8 lambdas. Yes, not every layperson would know what a lambda is. No, defining what it is isn't a need for an SO question to be perfectly fine - anyone of any appreciable level of expertise to be on SO should be able to google "lambdas java 8" even if they don't know anything about lambdas from their CS classes.