Saint Vincent and the Grenadines: noun: Saint Vincentian(s) or Vincentian(s)

adjective: Saint Vincentian or Vincentian

Samoa: noun: Samoan(s)

adjective: Samoan

San Marino: noun: Sammarinese (singular and plural)

adjective: Sammarinese

Sao Tome and Principe: noun: Sao Tomean(s)

adjective: Sao Tomean

Saudi Arabia: noun: Saudi(s)

adjective: Saudi or Saudi Arabian