a person who gives advice, especially somebody who knows a lot about a particular subject a financial adviser adviser (to somebody) (on something) a special adviser to the President on education See related entries: Unemployment, Banking, Job titlesExtra examples Do you have a financial adviser? She acts as an adviser to the president. Students can sit down with a careers adviser and discuss what to do next. The duke was the king’s most trusted adviser. You ought to consult an independent legal adviser. an adviser on environmental issues the government’s chief economic adviser the president’s most trusted adviser top foreign policy advisers As your legal adviser, it is my duty to warn you against it. He became one of the king’s closest and most trusted advisers. He was Chief Scientific Adviser to the government. He was a former US National Security Adviser.