1 Handle or control (a tool, mechanism, information, etc.) in a skilful manner.
1.1 Alter, edit, or move (text or data) on a computer.
1.2 Examine or treat (a part of the body) by feeling or moving it with the hand.
2 Control or influence (a person or situation) cleverly or unscrupulously.
2.1 Alter or present (data) so as to mislead.
Early 19th century back-formation from manipulation.
Mark manipulated his hammer imprecisely, hitting his own thumb instead of the nail.