What does potency mean?
Potency is a formal noun meaning the power, strength, or effectiveness of something. It is especially common in discussions of medicines, drugs, poisons, and other substances, where it describes how effectively a substance produces a particular effect. The word can also refer more generally to the force or intensity of an influence, as in the potency of a speech or the potency of an argument. A separate, formal sense concerns sexual capability or vigour. In medicine, potency has a technical meaning that should not be confused with potency as simply a synonym for strength: it concerns relative effectiveness and is often linked to dosage. Overall, potency conveys concentrated power or the capacity to have a strong effect, and its slightly technical tone distinguishes it from more informal expressions such as strength or power.
The power or strength of something to produce an effect, especially the effectiveness of a substance or medicine.
"The researchers compared the potency of the two compounds."
In pharmacology, this has a technical sense relating to the relative effect produced by a substance rather than merely the quantity present.
Power, force, or intensity of action or influence.
"The policy lost some of its potency after the new circumstances emerged."
This use is formal and is often associated with arguments, rhetoric, legislation, or other influences.
Sexual capability or vigour.
"The drug was advertised as a treatment for reduced potency."
This sense is formal and relatively uncommon in contemporary general English.
Used when referring to the different degrees of power or effectiveness of multiple substances, forces, or influences.
"The study compared the potencies of several natural compounds."
Potency comes from the same Latin root as potent and potential: something has power because it is potent, and possibility exists because it has potential.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Where does potency come from?
Potency comes from Latin potentia, meaning “power” or “strength,” derived from the adjective potens, meaning “powerful” or “capable.” English borrowed the word in the 15th century in senses connected with power and strength. Its relatives include potent, potential, and impotent, all of which reflect the same Latin root concerning power or capability.
Related word forms
How potency is actually used
In medicine and pharmacology, potency refers to the relative ability of a substance to produce an effect, and is distinct from the amount of a substance used. In general use, it often suggests concentrated strength or effectiveness. The sexual sense is usually formal and can sound somewhat clinical or humorous depending on context.
Easily confused with potency
Potency describes the strength or effectiveness something actually has, whereas potential refers to the capacity it might have to achieve something.