The imago is the last stage of development of an insect, after the last ecdysis of an incomplete metamorphosis, or after emergence from pupation where the metamorphosis is complete. As this is the only stage which is sexually mature, and has functional wings in winged species, the imago is often referred to as the adult stage.

The Latin plural of imago is imagines, and this is the term generally used by entomologists - however imagos or imagoes are also acceptable spellings.