To propose means to suggest an idea or plan for others to consider. When you propose something, you're putting forward a possibility: “I propose we have pizza for dinner” or “The student council proposed a new recycling program for the school.”

The word carries a sense of formality and seriousness. You might suggest getting ice cream after school, but you would propose a solution to a problem the class has been discussing. Scientists propose theories to explain what they observe. Lawmakers propose bills they want to become laws. When someone proposes an idea, they usually expect discussion and a decision, not just a casual “sounds good.”

The word has one special meaning that stands apart: to ask someone to marry you. When someone proposes marriage, they're asking another person to become their spouse, often with the traditional phrase “Will you marry me?” This is called a marriage proposal or simply a proposal.