He used the f double number sign k to express his frustration.

I need to double the number.

He's such a doubledome.

I saw a doubledecker bus on the street.

The doubledomes of the cathedral gleamed in the sunlight.

I saw two doubledeckers on the street.

Doubleday is a common surname in some English-speaking countries.

The Doubledays are a famous baseball team.

He is known for his doubledealing nature.