Entomology-The Science Of Insects, A Branch Of Zoology The Deals With The Origin Of Insects, Their Systematic Position, Morphology, Physiology Including Bodily Functions, Reproduction, Habit And Habitat, Behavior, Development And Their Economic Importance. In Wider Sense It Also Covers Study Of Losses Caused By Insect Pest To Crops (Agriculture Entomology, Their Prevention And Control ) (Plant Protection), Insect Pests Vis-À-Vis Forest Trees (Forest Entomology), Health And Hygiene (Medical Entomology, Forensic Entomology ) And Also Commercial Products Accruing From Certain Insects (Industrial Entomology) And (Veterinary Entomology).Although Insects Are Minute, The Problems Created By Them Are Of Large Magnitude And Their Solution Often Require Concerted Action On A Very Large Scale.Insects Appeared On The Scene Of Existence Some 250 To 500 Million Year Age While Man Entered The Scene Only About A Million Years Ago.The Dictionary Of Entomology Is Designed For Undergraduate And Post -Graduate Students Of Economic Entomology And Plant Protection .It Will Serve Guide To All Professor And Teachers Of Agriculture Universities And Also Progressive Cultivators, Orchard S And Plant Protection Workers.