Redbacks are a type of venomous spider found in Australia. While "redbacks" is the colloquial term for this spider, there are several synonyms that can be used to describe them. Some commonly used synonyms for redbacks include "Australian black widow," "Latrodectus hasselti," and "red hourglass spider." These terms are all used to describe the same arachnid species as redbacks, with variations in terminology depending on the region or scientific context. Despite the varying names, each term refers to a spider that is universally recognized as dangerous due to its potent neurotoxin.