Learn how to say Convections correctly in English with this tutorial pronunciation video.
Oxford dictionary definition of the word convection:
a process of heat transfer through a gas or liquid by bulk motion of hotter material into a cooler region Compare conduction (sense 1)
(meteorology) the process by which masses of relatively warm air are raised into the atmosphere, often cooling and forming clouds, with compensatory downward movements of cooler air
(geology) the slow circulation of subcrustal material, thought to be the mechanism by which tectonic plates are moved
C19: from Late Latin convectiō a bringing together, from Latin convehere to bring together, gather, from vehere to bear, carry