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thermos flask

thermos flask

3.4
A container that keeps drinks hot or cold for a long time
  • noun
  • /ˈθɜrməs flæsk/
translation icon : termo
  • To keep my tea warm during the day, I always carry a thermos flask.

Examples

  • She packed a thermos flask of ice water for the picnic.

  • There's only the thermos flask and the bottle.

  • We debated thermos flasks but went for simplicity.

  • I've got a quart and what's left in the thermos flask.

  • I filled my thermos flask with hot coffee before the long hike.

Synonyms

thermos
vsthermos flask
3 1.9

A container that keeps drinks hot or cold for a long time

is the general double-walled container for liquids beyond just drinks
thermos bottle
vsthermos flask
1 2.5

A bottle that keeps drinks hot or cold for a long time

is the broader term for this airless gap insulated bottle form
vacuum flask
vsthermos flask
4.2

A container that keeps drinks hot or cold for a long time

is the common household container mainly for keeping liquids hot or cold
vacuum bottle
vsthermos flask
3.7

A container with two walls and empty space between them that keeps drinks hot or cold

is a general container with double walls and an airless gap for liquids

How Insulating

thermos flask
3.4
bottle
1.0

Surface Forms

thermos flask singular

Morphology

thermos + flask

The meaning is directly and literally built from 'thermos' (a vacuum-sealed container for beverages) plus 'flask' (a container for liquids): together they specify a type of container that keeps liquids hot or cold. This is a straightforward compositional noun phrase common across languages, so a B1 learner who knows both constituents would understand the MWE.

Etymology

Thermos flask gets its name from the Greek word thermos, meaning 'hot', and from the simple bottle idea of a flask with two walls and an empty space between them. That empty space stops heat from moving in or out, so the bottle keeps drinks hot or cold for a long time.