In birds:

• Red-backed Button-quail (Turnix maculosus), species of bird in the Turnicidae family
• Red-backed hawk (Buteo polyosoma), species of bird of prey in the Accipitridae family
• Red-backed Fairy-wren (Malurus melanocephalus), species of bird in the Maluridae family, endemic to Australia
• Red-backed Kingfisher (Todiramphus pyrrhopygia), species of bird in the Alcedinidae family, endemic to Australia
• Red-backed Mousebird (Colius castanotus), species of bird in the Coliidae family
• Red-backed Shrike (Lanius collurio), species of bird in the Laniidae family
• Red-backed Thrush (Zoothera erythronota), species of bird in the Turdidae family

In other organisms

• Northern Redback Salamander (Plethodon cinereus), species of salamander found in eastn North America
• Southern Redback Salamander (Plethodon serratus), species of salamander found in the USA
• Redbacked jumping spider (Phidippus johnsoni), species of jumping spider found in North America
• Redback spider (Latrodectus hasselti), species of spider found in Australia
• Red-backed Bearded Saki (Chiropotes chiropotes), species of bearded saki found in South America
• Red-backed Toadlet (Pseudophryne coriacea), species of frog found in Australia
• Red-backed vole, several species of vole found in North America, Europe and Asia
• Grey Red-backed Vole (Myodes rufocanus)
• Hokkaido Red-backed Vole (Myodes rex)
• Korean Red-backed Vole (Myodes regulus)
• Northern Red-backed Vole (Myodes rutilus)
• Southern Red-backed Vole (Myodes gapperi)
• Tien Shan Red-backed Vole (Myodes centralis)
• Western Red-backed Vole (Myodes californicus)

In sport:

• Frankfurt Redbacks, Australian rules football club based in Frankfurt, Germany
• Glasgow Redbacks, Australian rules football club based in Glasgow, Scotland
• Southern Redbacks, Australian cricket team
• Romsey Football Club (nicknamed the "Redbacks"), Australian rules football club based in Romsey, Victoria, Australia

Other:

• Red Back Fever, 1991 album by The Angels
• Redback Networks, telecommunications equipment company
• Texas Redbacks, paper money issued between 1839 and 1840 in the Republic of Texas
• The Australian twenty dollar note, sometimes referred to as a redback