What prefix means "both" or "double"?

The prefix "ambi-" is derived from the Latin word meaning "both" or "on both sides." It is commonly used in medical and scientific terminology to denote duality or being present in two directions or forms. For example, the term "ambidextrous" refers to a person who can use both hands with equal skill.

The other prefixes have distinct meanings: "iso-" refers to equality or sameness, as seen in terms like "isotope," which indicates elements with the same number of protons but different neutrons. "Pseudo-" means false or deceptive; it is used in terms like "pseudoscience," indicating something that claims to be scientific but lacks empirical support. "Dys-" means bad, difficult, or abnormal, often used in terms like "dysfunction," which describes impaired or abnormal functioning. Therefore, "ambi-" is the appropriate prefix for conveying the meaning of "both" or "double."