dilute 1. To mix a powder, e.g. flour, with a liquid. 2. To add water to a concentrated liquid. Learn how to accurately dilute solutions with this simple guide. We explain how to calculate dilutions with a formula and how to make quick dilutions. If you dilute a substance you make it weaker or less pure by mixing it with another substance. Verb: To make a liquid thinner or weaker by adding water or another solvent. Adjective: Describing something that has been made less concentrated or potent. Dilute is involved with reducing strength, concentration, or intensity. It’s a common term in science, cooking, and even figurative language. The meaning of DILUTE is attenuate. How to use dilute in a sentence. DILUTE definition: to make (a liquid) thinner or weaker by the addition of water or the like. See examples of dilute used in a sentence. When you dilute something, you make it thinner, weaker, or more watered down. If you put lots of ice cubes in your soda, the ice will melt and dilute the drink. Think about diluting as lessening the quality but increasing the quantity. Verb dilute (third-person singular simple present dilutes, present participle diluting, simple past and past participle diluted) (transitive) To make thinner by adding solvent to a solution, especially by adding water. The simple definition of DILUTE is to make (a liquid) thinner or less strong by adding water or another liquid. If you dilute a substance you make it weaker or less pure by mixing it with another substance.