Definition of "borer" [bor•er]

• A tool used for drilling. (noun)
• An insect or insect larva, such as the corn borer, that bores into the woody parts of plants. (noun)
• Any of various mollusks that bore into soft rock or wood. (noun)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

• "The Watchdog says the word "ash borer" reminds him of his flea problem."
• "The borer is the despair of the land-owner; he works underground; no"
• "Unfortunately, the Emerald ash borer, which is attacking ash trees across the country, has been reported as near as the southwest corner of Wisconsin, right across the border from Dubuque, Iowa."