The Collaborative International Dictionary of English v.0.48:

Calvinism \Cal"vin*ism\, n. [Cf. F. Calvinisme.]
   The theological tenets or doctrines of John Calvin (a French
   theologian and reformer of the 16th century) and his
   followers, or of the so-called calvinistic churches.
   [1913 Webster]

   Note: The distinguishing doctrines of this system, usually
         termed the five points of Calvinism, are original sin
         or total depravity, election or predestination,
         particular redemption, effectual calling, and the
         perseverance of the saints. It has been subject to many
         variations and modifications in different churches and
         at various times.
         [1913 Webster]

WordNet (r) 3.0 (2006):

Calvinism
    n 1: the theological system of John Calvin and his followers
         emphasizing omnipotence of God and salvation by grace alone