(Australia, southeast Australia) The arrival of a cold front in the afternoon or evening after a day of high summertime temperatures. The arrival of the front often produces falls in temperature in the order of 10°C to 15°C and sometimes thunderstorm activity.

(intransitive) To decrease in temperature, activity, or temper. / (transitive) To cause to decrease in temperature, activity or temper.

(of a nuclear reactor) that uses liquid sodium as a coolant

(intransitive) To become cooler, to be reduced in temperature. / (transitive) To cause the temperature of an item to decrease. / (intransitive) To become less agitated.

(idiomatic) A person who performs or appreciates jazz, especially one whose style of speech and movement is relaxed and rhythmic.

(idiomatic) Before (an idea or activity) was popular, trendy, famous, or duly appreciated.

plural of cool tankard

(historical) A cooling drink of wine and water, with lemon juice, spices, and borage. / (UK, dialect) The plant borage itself.

plural of cool store

(Australia, New Zealand) a building or room that is kept cool for the storage of perishables (such as apples).