The American Heritage® Dictionary of the English Language, 4th Edition
n. Unselfish concern for the welfare of others; selflessness.
n. Zoology Instinctive behavior that is detrimental to the individual but favors the survival or spread of that individual's genes, as by benefiting its relatives.
n. Regard for others, both natural and moral; devotion to the interests of others; brotherly kindness; – opposed to egoism or selfishness.
the GNU version of the Collaborative International Dictionary of English
n. Regard for others, both natural and moral; devotion to the interests of others; brotherly kindness; -- opposed to egoism or selfishness.
The Century Dictionary and Cyclopedia
n. A term first employed by the French philosopher Comte to denote the benevolent instincts and emotions in general, or action prompted by them: the opposite of egoism.
WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
n. the quality of unselfish concern for the welfare of others
Word Usage
"This use of the term altruism makes it a very different thing from the quality or characteristic which in the West is described by this term."