A very fine starch powder derived from maize (US corn) used in cooking as a thickener, to keep things from sticking, or as an anti-caking agent.(noun)
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Use "cornflour" in a sentence
"Anyway, Australian cornflour is a flour made from dried corn."
"They are probably dusted in cornflour on the outside?"
"Other cold-swelling starches in the range are derived from maize and tapioca, which can be declared on labels as 'cornflour' and 'tapioca starch' respectively."