1. Any of numerous chiefly nonvenomous snakes of the family Colubridae, including the king snakes, garter snakes, and some water snakes.
2. Of, relating to, or belonging to the Colubridae.
3. Mostly harmless temperate-to-tropical terrestrial or arboreal or aquatic snakes.

A colubrid is a snake that is a member of the Colubridae family and it is a broad classification of snakes that includes well over half of all snake species on earth.

While most colubrids are non-venomous (or have venom that isn't known to be harmful to humans) and are normally harmless, some of the groups; such as, genus Boiga and sub-family Homalopsinae, can produce medically significant bites. In addition, the African Boomslang and African Twig Snake have both caused human fatalities.