Entomology definition of Exterior margin September 7, 2014 Raj Entomology Dictionary 0 Please Like Us!!! DesiGoogly.com > Education News > Entomology Dictionary > Entomology definition of Exterior margin Entomology definition of Exterior margin: the outer margin; sometimes used for costal margin. Entomology Exterior margin definitionExterior margin Entomology explanationExterior margin Entomology meaningReviews & Comments