conjecture

noun
  1. An opinion or conclusion formed on the basis of incomplete information. noun
    The detective's conjecture about the suspect's motive was based on circumstantial evidence.
    Her conjecture that the company would go bankrupt proved to be incorrect.
  2. To form an opinion or supposition about something on the basis of incomplete information. verb
    He conjectured that the meeting would be canceled due to the bad weather.
    Scientists conjecture that there might be life on other planets.