Definitions:

1. A container that is designed to keep drinks or food hot or cold for a prolonged period of time. NOUN
   • Thanks to the vacuum bottle, the tea stayed warm even after several hours in the cold weather.
2. An insulated container designed to maintain the temperature of its contents for extended periods. NOUN
   • I always bring my vacuum bottle to work to keep my coffee hot throughout the day.
3. Flask with double walls separated by vacuum, used to maintain substances at high or low temperatures. NOUN
   • The vacuum bottle effectively maintains the temperature of beverages for hours.

Synonyms:

• thermos
• vacuum flask