Webster's New World College Dictionary Copyright © 2010 by Wiley Publishing, Inc., Cleveland, Ohio.
noun pl. gallflies
an insect whose eggs or larvae cause galls when deposited in plant stems, or one which lays its eggs in galls produced by other insects
Used by arrangement with John Wiley & Sons, Inc.
The American Heritage® Dictionary of the English Language, 4th edition Copyright © 2010 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Any of various small insects, such as the gall midge or gall wasp, that deposit their eggs on plant stems or in the bark of trees, causing the formation of galls in which their larvae grow.