What does dilution mean?
Dilution is the act or process of making something weaker or less concentrated, most literally by adding water or another solvent to a liquid. In a laboratory, dilution is a routine procedure: adding distilled water to a concentrated acid or dye reduces its strength to a precise, usable level. Beyond chemistry, the word extends naturally into business and everyday language. In finance, dilution refers to the reduction in an existing shareholder's proportional ownership that occurs when a company issues new shares. Figuratively, dilution describes any loss of potency, purity, or distinctiveness — the dilution of a brand's image, of academic standards, or of an argument's force. The word carries a mildly negative connotation in these figurative uses, implying that something valuable has been spread too thin or compromised. Its opposite, concentration, captures what is lost: intensity, density, and effect.
nounThe action or process of making a liquid thinner or weaker by adding water or another solvent to it. By extension, the weakening or reduction in force, value, quality, or effectiveness of something.
- The process of reducing the concentration of a substance, especially a liquid, by adding a solvent such as water.
- The reduction of ownership percentage or voting power of existing shareholders caused by the issuance of new shares.
- A general weakening or diminishing of the strength, value, purity, or effectiveness of something abstract, such as standards, brand identity, or an argument.
"The chemist warned that even slight dilution of the reagent would skew the results."
"Follow the recipe carefully; too much dilution will leave the sauce flavorless."
"Investors worried about dilution after the company announced another round of share issuance."
"Critics complained that the sequel's broad appeal came at the cost of a noticeable dilution of the original's dark tone."
The plural is used mainly when referring to multiple prepared mixtures of differing concentrations, or to several instances of the weakening process; in abstract or general senses the singular is far more common.
"The lab technician prepared a series of serial dilutions for the assay."
In homeopathy, some remedies are diluted so many times that not a single molecule of the original substance remains — yet believers still credit them with healing power.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of dilution
Dilution derives from the Latin verb 'diluere', meaning 'to wash away' or 'to dissolve', formed from the prefix 'dis-' ('apart') and 'luere', from 'lavare', meaning 'to wash'. The related English adjective 'dilute' entered the language in the mid-16th century, with 'dilution' following as its noun form shortly thereafter, initially in scientific and alchemical contexts before broadening into financial and figurative use. The same Latin washing root gives us words such as 'lavish', 'lava', and 'ablution', all carrying the underlying sense of washing or flowing.
Related word forms
How dilution is actually used
Dilution is a formal to neutral register noun used across chemistry and laboratory science (its literal core sense), corporate finance (equity dilution), and figurative contexts describing weakened quality or impact. In finance it often carries a negative connotation for existing shareholders, since their stake becomes proportionally smaller. The figurative sense is common in criticism of media, brands, and institutions.
Easily confused with dilution
A delusion is a false belief held despite evidence, while dilution is the process of thinning or weakening a substance — they sound alike but are unrelated in meaning.