1. a small flat bottle, typically made of metal, used for carrying liquor
2. a narrow-necked glass container used in laboratories
Usage: scientific
3. a vacuum bottle or thermos for keeping liquids hot or cold

Examples

• He pulled a silver flask from his coat pocket.
• The hiker carried a flask of hot coffee on the mountain trail.
• The chemistry student heated the solution in a glass flask.
• She used an Erlenmeyer flask for the experiment.
• The thermos flask kept the soup warm all day.
• The flask contained enough water for the short hike.