[wvbdmp]

Before the American meaning became ubiquitous, corn used to mean (and still does sometimes) just any grain. In fact it also survives in other languages like German, where “Korn” is a singular kernel, or an uncountable amount of grain, as well as the figurative meaning in “film grain”.

[VorpalWay]

In Swedish "korn" is a specific species of grain (called barley in English). For grains in general we use the term "sädesslag".