In English, there are only three commonly used words with two continuous 'U's,
1. 'Residuum' meaning residue.
2. 'Vacuum' meaning a space completely devoid of matter.
3. 'Continuum' meaning a thing having a continuous structure.
He threw the residuum of the juice in the dustbin.
The residuum of distillation of crude oil is used as grease or semi-solid lubricants.
The residuum of craft works can also be used creatively.
Light can travel in vacuum.
Moon has no atmosphere, it is vacuum over there.
The food packets are vacuumed to avoid oxidation.
In Diwali, the houses shone with a continuum of candles.
Their strategy to make a continuum and fight against the army was successful.
The hall was fenced with the continuum of chains.