Let's extract the political definitions from Websters, which is the gold standard for American English.

http://www.m-w.com/dictionary/liberalism
"a political philosophy based on belief in progress, the essential goodness of the human race, and the autonomy of the individual and standing for the protection of political and civil liberties"

http://www.m-w.com/dictionary/conservatism
" a political philosophy based on tradition and social stability, stressing established institutions, and preferring gradual development to abrupt change"

>Start here:
>
>Definitions of conservatism on the Web:
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> * a political or theological orientation advocating the preservation of the best in society and opposing radical changes
> wordnet.princeton.edu/perl/webwn
>
> * Conservatism is any of several historically-related political philosophies or political ideologies. There are also a number of Conservative political parties in various countries. They usually identify with the political right.
> en.wikipedia.org/wiki/Conservatism
>
> * A political philosophy or attitude that emphasises respect for traditional institutions, distrust of government activism and opposition to sudden change in the established order.
> www.channel4.com/history/microsites/H/history/browse/glossary.html
>
> * Constancy with time of a given physical property during a specific process.
> amsglossary.allenpress.com/glossary/browse
>
> * This is a term that is almost impossible to define. Classical conservatism as set forth by Burke stresses continuity and a preservation of our present institutions for fear that change could awaken the tempests and undermine the fragile social order. Contemporay conservatism, in the US, is often distinguished by talk of radical change if not revolution. ...
> www.wiu.edu/users/mfcjh/wiu/class/glossary/glossar1.htm
>
> * Preference for the existing order of society. An opposition to all efforts to bring about rapid or fundamental change. A belief that existing economic and political inequalities are well justified and that the existing order is about as close as is practically attainable to an ideal order. Conservatives often base their claims on the teachings of religion and/or traditional morality and tend to downplay the social theories by secular philosophers, economists, and other social thinkers.
> www.information-entertainment.com/Politics/polterms.html
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> * A political ideology generally characterized by a belief in individualism and minimal government intervention in the economy and society; also a belief in the virtue of the status quo and general acceptance of traditional morality.
> www.comune.venezia.it/atlante/documents/glossary/nelson_glossary.htm