hypothesis

noun
  1. A supposition or proposed explanation made on the basis of limited evidence as a starting point for further investigation. noun
    The scientist formulated a hypothesis to explain the strange phenomenon.
    Her hypothesis was that the plant would grow faster in direct sunlight.
  2. An idea or theory that is not proven but that leads to further study or discussion. noun
    The hypothesis that life exists on other planets has fascinated scientists for decades.
    He proposed a hypothesis about the effects of pollution on marine life.