The antonyms for "opened out" can be phrases like "closed in," "shrunk down," or "contracted." These terms refer to a state of being where space is limited, confined, or restricted. Another antonym could be "narrowed" which implies a reduction in width or space. "Concealed" or "hidden" could also be used as antonyms as they suggest that something is not visible or accessible. These terms are particularly useful when describing the opposite of a space that has been opened out, such as a room that has been made smaller, or a path that has been narrowed.