A more general definition might describe it as the forward motion resulting from applying a driving force behind something. (ameslab.gov)
In general definition, Contract law is a legal agreement associated with the goods, services, money or property between two or more parties, the violation of which leads to filing a case against the accused party. (instantassignmenthelp.com)
The most general definition of power is in Paul Tillich's Love, Power and Justice (Oxford): «Power is being actualizing itself over against the threat of non-being.» (religion-online.org)