Reasonable ground means a justifiable or valid basis for belief or action. Some synonyms for this term include probable cause, valid reason, legitimate grounds, logical justification, plausible explanation, rational basis, and sound basis. These words convey the idea that there is evidence or information that supports a particular belief or conclusion. In legal terms, reasonable ground often refers to the evidence that is required to support a warrant or arrest. In everyday language, it is used to describe a situation in which a person has a justifiable reason to believe or do something. Having reasonable ground for belief or action is important because it ensures that decisions are based on evidence and reason rather than speculation or bias.