O·pen v. t. [imp. & p. p. Opened p. pr. & vb. n. Opening.]
 1. To make or set open; to render free of access; to unclose; to unbar; to unlock; to remove any fastening or covering from; as, to open a door; to open a box; to open a room; to open a letter.
 And all the windows of my heart
 I open to the day.   --Whittier.
 2. To spread; to expand; as, to open the hand.
 3. To disclose; to reveal; to interpret; to explain.
    The king opened himself to some of his council, that he was sorry for the earl's death.   --Bacon.
    Unto thee have I opened my cause.   --Jer. xx. 12.
    While he opened to us the Scriptures.   --Luke xxiv. 32.
 4. To make known; to discover; also, to render available or accessible for settlements, trade, etc.
    The English did adventure far for to open the North parts of America.   --Abp. Abbot.
 5. To enter upon; to begin; as, to open a discussion; to open fire upon an enemy; to open trade, or correspondence; to open an investigation; to open a case in court, or a meeting.
 6. To loosen or make less compact; as, to open matted cotton by separating the fibers.
 To open one's mouth, to speak.
 To open up, to lay open; to discover; to disclose.
    Poetry that had opened up so many delightful views into the character and condition of our =\“bold peasantry, their country's pride.”\=   --Prof. Wilson.