pacifism n.

1540s, "tending to make peace, concillatory," from French pacifique, from Latin pacificus "peaceful, peace-making," from pax (genitive pacis) "peace" (see peace) + combining form of facere "to make" (from PIE root *dhe- "to set, put"). Meaning "peaceful, characterized by peace or calm" is recorded from 1630s. Related: Pacifical (mid-15c., "of a peaceful nature"); pacifically.

Pacific, making or desiring to make peace; peaceable, desiring to be at peace, free from the disposition to quarrel; peaceful, in a state of peace. [Century Dictionary, 1895]

The Pacific Ocean (1660 in English) was famously so called in 1519 by Magellan when he sailed into it and found it calmer than the stormy Atlantic, or at least calmer than he expected it to be. According to an original account of the voyage by an Italian named Pigafetta, who was among the adventurers, Magellan gave the entrance to what Pigafetta calls "the South Sea" the Latin name Mare Pacificum.  The U.S. Pacific Northwest is so called by 1889.

1904, "pacifism, rejection of war and violence as a matter of principle," 1904, from pacific + -ism. Fowler, in 1926, wrote that the longer form was better, "but its chances of ousting the wrong form are small."

But pacificism gradually evolved a sense distinct from pacifism, "advocacy of a peaceful policy as a first resort or in a particular instance." Since the 19th century the international peace movement has included absolutists (who believe war can be totally and immediately repudiated) and moderates who see the abolition of war as a gradual process of promoting international systems and reforming nations and who believe that, until then, defensive military force may be needed to protect reforms. The use of pacificist for the latter was suggested in 1957 by British historian and nuclear-disarmament activist A.J.P. Taylor. Related: Pacificist.

"proponent or advocate of pacifism," 1903, from French pacifiste (see pacifism). Related: Pacifistic (1902).