1819, type of Indian corn suitable for popping, from pop (v.) + corn (n.1). To pop corn "parch or roast corn kernels until they burst open" is by 1847.
Entries linking to popcorn
pop v.
mid-15c., "to strike so as to cause to make a short, quick sound;" intransitive sense "make a short, quick sound" is from 1570s; imitative. Of eyes, "to protrude" (as if about to burst), from 1670s. Sense of "to appear or to put with a quick, sudden motion" (often with up, off, in, etc.) is recorded from mid-15c. Baseball sense of "to hit a ball high in the air" is from 1867. To pop the question is from 1725, specific sense of "propose marriage" is from 1826. Related: Popped; popping.
corn n.1
"grain," Old English corn "single seed of a cereal plant; seeds of cereal plants generally; plants which produce corn when growing in the field," from Proto-Germanic *kurnam "small seed" (source also of Old Frisian and Old Saxon korn "grain," Middle Dutch coren, German Korn, Old Norse korn, Gothic kaurn), from PIE root *gre-no- "grain."
The sense of the Old English word was "grain with the seed still in" (as in barleycorn) rather than a particular plant. Locally understood to denote the leading crop of a district. It has been restricted to the indigenous "maize" in America (c. 1600, originally Indian corn, but the adjective was dropped), usually "wheat" in England, "oats" in Scotland and Ireland, while Korn means "rye" in parts of Germany.
Maize was introduced to China by 1550, it thrived where rice did not grow well and was a significant factor in the 18th century population boom there. Corn-starch is from 1850. Corn-silk is attested from 1852.