Definition of "only if" []

• Not unless; used to introduce a necessary condition. (conjunction)

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• "Similar to Lyndon Johnsons Tuesday lunches, the structure could have worked, but only if it had adequate staffing support to prepare meetings and ensure that decisions would be implemented."
• "In Banon's case, an investigation would begin only if her attempted rape complaint is found to be false."
• "One day, when Alexander was asked if he would be willing to compete in the footrace at the upcoming Olympic games, the prince replied that he would, but only if he could compete against kings."