You can add your own translations by placing a region-specific translation file in a
craft/translations folder. The filename should be named after your locale and return an array of translations. In your case this may look like a file named:
And within that file, returning an array like so:
"Singles" => "Something Better than Egyedülállók"
All strings that are identified as translatable in your front-end templates and the Craft Control Panel files, will be checked against these translations when loading a page in your particular locale. Craft's help doc on Static Translations discusses what this could look like in your templates.
If the phrase is really off in your language, you may want to reach out to Pixel & Tonic and let them know as well. I believe they welcome recommendations from community members on how language translations can be improved.