The term 'SMALL VIPER' is composed of two crossword solutions, ASP (3 letters) and ADDER (5 letters). ASP is an acronym for the venomous snake species, 'Vipera aspis', which is found in Europe and North Africa. ADDER is another name for the same species, and is derived from the Old English word 'næddre'. Both terms refer to a small viper, which is a type of venomous snake that is typically found in temperate climates.