According to Black's Law Dictionary, 8th ed., probate is defined as:
- to admit (a will) to proof,
- to administer a decedent's estate, or
- to grant probation to a crmiinal; to reduce a sentence by means of probation
The third definition isn't applicable to our discussion so we can ignore it. When most people say "Probate" by itself, they are referring to the second definition, "to administer a decedent's estate", which can include the first definition, assuming the decedent died with a will. But, because not everyone dies with a will, the second definition is the better definition.
So, probate means the process of administering a decedent's estate, whether in court or out of court.