corn borer
noun
: any of several insects that bore in the stalks or ears of corn: such as
a
: an Old World moth (Ostrinia nubilalis) widespread in eastern and central North America where its larva is a major pest in the stems, crowns, and fruits of crop plants and especially corn
called also European corn borer
b
: a pyralid moth (Diatraea grandiosella) whose larva causes serious damage especially to corn crops by boring in the stalks
called also southwestern corn borer
Example Sentences
Recent Examples on the Web Per the Guardian, the male corn borer moth copies the sounds of predatory bats, which stops the female moth cold and gives the male a moment to swoop in and mate with her. 
Alex Fox, Smithsonian Magazine, 3 Mar. 2021 Farmers with corn borers to control next year should plan to attend the plowing demonstration to be held on George and Leon Bailey farm on Thursday, September 24, at 1:30 p.m. Leon Bailey, the operator of the farm. Kitty Conley, Post-Tribune, 11 Sep. 2017
Alex Fox, Smithsonian Magazine, 3 Mar. 2021 Farmers with corn borers to control next year should plan to attend the plowing demonstration to be held on George and Leon Bailey farm on Thursday, September 24, at 1:30 p.m. Leon Bailey, the operator of the farm. Kitty Conley, Post-Tribune, 11 Sep. 2017 Word History
First Known Use
1853, in the meaning defined above