資料來源 : Webster's Revised Unabridged Dictionary (1913)

   3. Rendering probable; supporting, or giving ground for,
      belief, but not demonstrating; as, probable evidence;
      probable presumption. --Blackstone.

   {Probable cause} (Law), a reasonable ground of presumption
      that a charge is, or my be, well founded.

   {Probable error} (of an observation, or of the mean of a
      number), that within which, taken positively and
      negatively, there is an even chance that the real error
      shall lie. Thus, if 3[sec] is the probable error in a
      given case, the chances that the real error is greater
      than 3[sec] are equal to the chances that it is less. The
      probable error is computed from the observations made, and
      is used to express their degree of accuracy.

資料來源 : WordNet®

probable cause
     n : (law) evidence sufficient to warrant an arrest or search and
         seizure; "a magistrate determined that there was probable
         cause to search the house"