convection
n. uncountablen. the way heat moves through liquids or gases. It happens because warmer, lighter parts rise and cooler, heavier parts sink.
n. the transfer of heat through the bulk movement of molecules within fluids, such as gases and liquids. Driven by density gradients resulting from temperature variations.
The soup heats up quickly because of convection.
In a kitchen, a convection oven uses a fan to circulate hot air and cook food more evenly.
The Earth's tectonic plates are driven by slow-moving convection currents within the mantle, where heat from the core causes molten rock to rise and then cool as it nears the crust.
From Latin convectiōnem, from convectiō (“act of carrying”), from convect-, past participle stem of convehō (“to carry together”), combination of com- and vehō.
Often appears in the compound 'convection current' or as a modifier in 'convection oven'.