Beetles (Coleoptera) are an order of holometabolous insects with elytra protecting their wings. The word "beetle" comes from the Greek κολεός " sheath " and πτερόν " wing ". This is the animal order with the largest number of species described (nearly 387,000 described in 2015 1 but the total number, based on statistical estimates, is estimated at 1.5 million species 2 ).

Many species or groups of species have well-established vernacular names; beetles , ladybirds , lucanes , leaf beetles , beetles , weevils , ground beetles , leptures , for example, are beetles.