When editing a date on Wikidata, it's possible to indicate the level of precision (day, year, etc.)
The variable is not yet added to Translatewiki, which means that the names day, year, etc. remains in English even if the user is using another language. We should have it as a translatable variable, so the community can provide translations.
Example in French ("day" is still in English)
To check the difference with the other parts of the interface: click on https://www.wikidata.org/wiki/Q4115189?uselang=qqx and try editing a date.