There are two types of partners. General partners have an obligation of strict liability to third parties injured by the Partnership. General partners may have joint liability or joint and several liability depending upon circumstances. The liability of limited partners is limited to their investment in the partnership.
A silent partner is one who still shares in the profits and losses of the business, but who is uninvolved in its management, and/or whose association with the business is not publicly known; these partners usually provide capital.
http://en.wikipedia.org/wiki/Partnership

One that makes financial investments in a business enterprise but does not participate in its management.
http://www.answers.com/topic/silent-partner