Saint Lucia conventional long form: none conventional short form: Saint Lucia

Saint Pierre and Miquelon conventional long form: Territorial Collectivity of Saint Pierre and Miquelon conventional short form: Saint Pierre and Miquelon local long form: Departement de Saint-Pierre et Miquelon local short form: Saint-Pierre et Miquelon

Saint Vincent and the Grenadines conventional long form: none conventional short form: Saint Vincent and the Grenadines

Samoa
conventional long form: Independent State of Samoa
conventional short form: Samoa
local long form: Malo Sa'oloto Tuto'atasi o Samoa
local short form: Samoa
former: Western Samoa

San Marino
conventional long form: Republic of San Marino
conventional short form: San Marino
local long form: Repubblica di San Marino
local short form: San Marino

Sao Tome and Principe conventional long form: Democratic Republic of Sao Tome and Principe conventional short form: Sao Tome and Principe local long form: Republica Democratica de Sao Tome e Principe local short form: Sao Tome e Principe

Saudi Arabia
conventional long form: Kingdom of Saudi Arabia
conventional short form: Saudi Arabia
local long form: Al Mamlakah al Arabiyah as Suudiyah
local short form: Al Arabiyah as Suudiyah

Senegal
conventional long form: Republic of Senegal
conventional short form: Senegal
local long form: Republique du Senegal
local short form: Senegal
former: Senegambia (along with The Gambia); Mali Federation

Serbia
conventional long form: Republic of Serbia
conventional short form: Serbia
local long form: Republika Srbija
local short form: Srbija
former: People's Republic of Serbia, Socialist Republic of Serbia

Seychelles
conventional long form: Republic of Seychelles
conventional short form: Seychelles
local long form: Republic of Seychelles
local short form: Seychelles