1. To move, arrange, operate, or control by the hands or another body part or by mechanical means, especially in a skillful manner: She manipulated the lights to get just the effect she wanted. See Synonyms at handle.

2. To influence or manage shrewdly or deviously: He manipulated public opinion in his favor.

3. To tamper with or falsify for personal gain: tried to manipulate stock prices.

4. Medicine To handle and move in an examination or for therapeutic purposes: manipulate a joint; manipulate the position of a fetus during delivery.