Middle English, from Anglo-French changer, from Latin cambiare to exchange, probably of Celtic origin; akin to Old Irish camm crooked


  • 1.a : to make different in some particular : alter <never bothered to change the will>
b : to make radically different : transform <can't change human nature>
c : to give a different position, course, or direction to
  • 2.a : to replace with another <let's change the subject>
b : to make a shift from one to another : switch <always changes sides in an argument>
c : to exchange for an equivalent sum of money (as in smaller denominations or in a foreign currency) <change a 20-dollar bill>
d : to undergo a modification of <foliage changing color>
e : to put fresh clothes or covering on <change a bed>
For lessons on Change, follow this link.


A stimulus or force causes change. For example, ice melts into water. The heating of the ice above 32 degrees Fahrenheit caused the immobile oxygen and hydrogen atoms to mobilize, changing the ice into water.

Throughout history, change has been defined by varying points of view. In ancient Greek philosophy, while Heraclitus saw change as ever-present and all-encompassing, Parmenides virtually denied its existence. One's philosophical position may have an influence on the perception of change.

Isaac Newton and Gottfried Leibniz harnessed mathematical concepts into calculus to provide mathematical models of change. This constituted a major step forward in understanding flux and variation. In modern physics, the concept of change is associated with action.


Medieval thought fostered great respect for appeal to authority and revelation, severely cramping any encouragement of change.

With the rise of Industrial revolution and capitalism, the importance attached to innovation grew, and social and political upheavals and pressures often forced change by violent revolution (as in North America in the late 18th century and in later imitators). By the late 20th century much business and New Age thought focused enthusiastically on transformation in management, in function and in mental attitudes, while ignoring or deploring changes in society.

Changes in society have been observed through slow, gradual modifications in mindsets and beliefs as well as through dramatic action (see revolutions). History is one of the tools used to document change.