any moth of the family sphingidae, of which there are numerous genera and species. they are large, handsome moths, which fly mostly at twilight and hover about flowers like a humming bird, sucking the honey by means of a long, slender proboscis. the larvae are large, hairless caterpillars ornamented with green and other bright colors, and often with a caudal spine. see sphinx, also tobacco worm, and tomato worm.