any of numerous swift-flying, often large, dipterous insects of the family Asilidae that are predaceous on other insects.
Origin of robber fly
First recorded in 1870–75
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
any of the predatory dipterous flies constituting the family Asilidae, which have a strong bristly body with piercing mouthparts and which prey on other insectsAlso called: bee killer, assassin fly
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012