1. Small containers, typically made of glass or metal, used for carrying or storing liquids
She packed several flasks of water for the hiking trip.
Ela empacotou vários frascos de água para a caminhada.
2. Metal or glass bottles with a narrow neck, commonly used in laboratories for chemical experiments
The chemistry student filled the flasks with different solutions.
A aluna de química encheu os frascos com diferentes soluções.
3. Thermal containers, often called vacuum flasks or thermos flasks, used to keep liquids hot or cold
We brought hot coffee in flasks to keep warm during the winter picnic.
Levamos café quente em garrafas térmicas para manter o calor durante o piquenique de inverno.