estimate

noun
  1. An approximate calculation or judgment of the value, number, quantity, or extent of something. noun
    The contractor gave us an estimate for the cost of the renovations.
    According to the latest estimate, the population of the city has grown by 5%.
  2. To roughly calculate or judge the value, number, quantity, or extent of something. verb
    She estimated the distance to be about three miles.
    The scientist estimated that the experiment would take three weeks to complete.