Dictionary.net

• Proceeding only from one part or side of a matter in question; one-sided; partial; as, an ex parte statement: specifically, in law, applied to any step taken by or on behalf of one of the parties to a suit or in any judicial proceeding, in the absence of the other; as, an ex parte application; an ex parte hearing; ex parte evidence: hearings before grand juries are ex parte.

1899 - The american dictionary of the english language.
By Daniel Lyons