Sentence:  Prior to seeing him and meeting him, and hearing him speak, I had conjured up a <WSD>picture</WSD> of him in my mind, which actual contact with him proved to be an illusion. I had conceived of him...as being tall, commanding, and as the advance notices of him, a sliver-tongued orator. I found him, however, to be the opposite of my mental <WSD>picture</WSD>; short, squat, unpretentiousnb.... 
Meaning of the word marked with <WSD> tags:  An image; a representation as in the imagination.