Node.js getaddrinfo ENOTFOUND

In Node.js HTTP module's documentation: http://nodejs.org/api/http.html#http_http_request_options_callback

You can either call http.get('http://eternagame.wikia.com/wiki/EteRNA_Dictionary', callback), the URL is then parsed with url.parse(); or call http.get(options, callback), where options is

{
  host: 'eternagame.wikia.com',
  port: 8080,
  path: '/wiki/EteRNA_Dictionary'
}

Update

As stated in the comment by @EnchanterIO, the port field is also a separate option; and the protocol http:// shouldn't be included in the host field. Other answers also recommends the use of https module if SSL is required.

Another common source of error for

Error: getaddrinfo ENOTFOUND
    at errnoException (dns.js:37:11)
    at Object.onanswer [as oncomplete] (dns.js:124:16)

is writing the protocol (https, https, ...) when setting the host property in options

  // DON'T WRITE THE `http://`
  var options = { 
    host: 'http://yoururl.com',
    path: '/path/to/resource'
  }; 

in the options for the HTTP request, switch it to

var options = { host: 'eternagame.wikia.com', 
                path: '/wiki/EteRNA_Dictionary' };

I think that'll fix your problem.

My problem was that my OS X (Mavericks) DNS service needed to be restarted. On Catalina and Big Sur DNS cache can be cleared with:

sudo dscacheutil -flushcache; sudo killall -HUP mDNSResponder

Older macOS versions see here.