Key Difference: Corn and maize are used interchangeably. Corn primarily means maize which is used among North Americans. It was derived from the Germanic word ‘kurnam’. Maize is another name for corn. It was derived from the Ancient word 'mahiz' from the Taino language. American corn is referred to more specifically in the U.K. as maize.

Corn and maize are synonyms. Maize is another name for corn. See the difference Baby corn Vs. Sweet Corn.

Corn primarily means maize which is used among North Americans. Corn was derived from the Germanic word ‘kurnam’. The word has traditionally been used to denote the primary grain crop in a specified area. When Europeans were introduced to maize, they called it as ‘corn’. The usage of this term is more for Indian corn. Corn is mais in Spanish, mais in French, mais in Italian, and mais in German. The pattern is developing in many countries. It is believed that corn is more preferred to be used for food products such as corn flour, corn meal, corn syrup, corn oil, etc. See the difference Corn Vs. Sweet Corn.  

Maize is another name for corn. It was derived from the Ancient word 'mahiz' from the Taino language. American corn is referred to more specifically in the U.K. as maize. It is a grain that is grown in huge quantities throughout the world. Corn kernels are the seeds of maize. Though technically a grain, maize kernels are used in cooking as a vegetable or starch. Indian corn has varieties of maize and is young and fresh to eat. These corns have variably colored kernels and are perfectly edible. Maize is a versatile crop and can be grown in a number of different continents. 

Today, the terms corn and maize are used interchangeably, as both are types of grain with one being used more commonly than the other in certain regions or contexts, though in some European countries “corn” may also refer to wheat or barley.
See the difference Corn flour Vs. Cornstarch. 

Difference between Corn and Maize: 

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