As a Noun: 1. All the facts about something, rather than things that are imagined or invented. English = truth. 2. A piece of information that is true. English = fact. 3. The world around us as it is rather than the way someone imagines it to be. English = reality. As a Verb or Adjective: 1. To be based on facts and on things that really have happened and are not invented. English = (be) true, (be) factual, (be) real. 2. To have no doubt that something is in agreement with the facts, to have no doubt that something is true. English = (be) sure, (be) certain. 3. To be firm and clear, and be unlikely to be changed. English = (be) definite. 4. To believe that someone is honest, is telling the truth and will not deliberately do anything to harm you. English = trust. Interactive: 1. Used alone in response to your addressee's comments to show that you agree with what they have said. English = 'True!', 'Yes, indeed!', 'Absolutely'. As Modifier: 1. Used before some signs to add emphasis to what you are saying. English = truly, such, absolutely. 2. In mathematics, used before the sign INTEGRAL to mean ‘definite integral’. A definite integral has start and end values (a, b) which define an interval. The values a and b are the limits, bounds or boundaries of the integral and are written at the top and bottom the the integral symbol.