What is tetra meaning?

Tetra is a term used to refer to a group of small freshwater fish belonging to the Characidae family. These fish are native to South America and are known for their colorful appearance and ease of care, making them popular among aquarium enthusiasts. Some popular tetra species include the neon tetra, cardinal tetra, and cherry barb. The name "tetra" comes from the Greek word "tetras," which means four, referring to the four unpaired fins that these fish possess.