The initial idioms of the letter S

Social Democratic Party	Social Development Commission
social disease	social drinker
social event	social function
social gathering	social group
social insect	social insurance
social intercourse	social lion
social movement	social occasion
social organisation	social organization
social phobia	social policy
social process	social psychology
social rank	social reformer
social relation	social science
social scientist	social season
social secretary	Social Security
Social Security Administration	Social Security number