Name the most commonly-spoken languages which are not the official or de facto official language of any country.
Speakers from Ethnologue200.
Official languages from Wikipedia.
Language boundaries (ex. Hindi and Urdu) are fluid. I've made what I (a linguistic anthropologist) feel are common-sense adjustments. Feel free to discuss in the comments.
For one of these, a common name for the language has been excluded because it's also a broad linguistic term.