1) Type of viper 
(from the article `Cerastes`) genus of venomous, desert-dwelling snakes of the viper family, Viperidae. There are two species, the horned viper (C. cerastes), which usually has a ... The three species of Old World sidewinders are pitless vipers (subfamily Viperinae) of the genus Cerastes. Two of them (C. cerastes and C. vipera) ... [...
[n] - highly venomous viper of North Africa and southwest Asia having a horny spine above each eye
cerastes noun highly venomous viper of northern Africa and southwestern Asia having a horny spine above each eye
a highly venomous viper, Cerastes cerastes, of northern Africa and extreme southwestern Asia, having a process resembling a horn just above each eye.