Thermos (noun)

A vacuum flask used to keep liquids hot or cold.

Origin:

From the greek thermos meaning "hot".

Examples:

1. I always bring my thermos filled with hot chocolate to work.
2. She packed a thermos of iced tea for their picnic.
3. The thermos kept the soup hot for hours.
4. The thermos is an essential piece of camping gear.
5. He reached for the thermos to pour himself a cup of coffee.