social democrat

a person who advocates a gradual transition to socialism or a modified form of socialism by and under democratic political processes.

Social Democrat. (especially in Europe) a member of any of certain Social Democratic parties.

Origin of social democrat

First recorded in 1875–80

On Wednesday, the social-democrat named fellow moderates to key economic posts at Finance, Labor, Budget, and Social Affairs.

French President François Hollande Goes to Washington |Tracy McNicoll |May 18, 2012 |DAILY BEAST
The social-democrat now becomes the principal opponent to President Nicolas Sarkozy's reelection bid next spring.

Can Sarkozy Survive? |Tracy McNicoll |October 17, 2011 |DAILY BEAST
Against his will, for he was a social-democrat, he accepted the offer.

The History of Yiddish Literature in the Nineteenth Century |Leo Wiener
It follows that the time spent in prison and exile is about one-third of the time a Social-Democrat is active.

Our Revolution |Leon Trotzky

A weekly paper, the Social-Democrat, was established at Zrich.

Encyclopaedia Britannica, 11th Edition, Volume 11, Slice 8 |Various

social democrat

any socialist who believes in the gradual transformation of capitalism into democratic socialism

(usually capital) a member of a Social Democratic Party