Schisma Barcinonicum - A Schismatic From Barcelona (Pope Anti-pope Clement VIII (1423-1429) motto, according to St. Malachy prophecies - He was a Canon of Barcelona)
Sciencia et Cultura pro omine - Science and culture at the service of man (Academic term - University Motto)
Scientia et praxis - Science and practice (Motto of the Lima University in Peru)
Scientiam et veritatem et iustitiam doce me - Science and Truth and Justice will teach me (Academic term - Original motto of Lima University, Peru)
Scire ad trascendere - Learn to transcend (Academic term - Motto of Zalapa University in Veracruz, Mexico)
Se lumen proferre - Let the light shine forth (Academic term - Motto of Aguascalientes University in Mexico)
Securitas est futurus - Security is future (Motto of the Air traffic controllers in Paraguay)
Semper Alere Flammam - Always feeding the flame (Motto of prep school #8 of the University of Nuevo Leon, Mexico)
Semper Ascendens - Always Ascending (Motto of State of Nuevo Leon, Mexico)
Semper deinceps - Always forward (Motto of GA-935 JROTC raider team - Thank you: Kendall)
Semper Fidelis - Always Faithful (Marine Corp Motto)
Semper gumby - Always flexible (Motto of the US Air Force - This sentence is a hack, it is evident that "gumby" is not Latin)
Semper Paratus - Always Ready (Motto of the United States Coast Guard - Thank you: E. Oleson)
Semper primus - Always first (Motto of the US Navy)
Serviendo guberno - I govern by serving (Family motto of nobility i.e. O'Rourkes of Ireland - Thank you: Charlie)
Sic itur ad astra - This is the way to the stars (Motto of the Colombian Air Force)
Sic Luceant Opera Tua - Your work continues to shine (Motto of the city of Gandia in Valencia, Spain)
Sic obvia frangit - This overcomes obstacles (Motto of the Spanish Light Armoured Cavalry Regiment #11)
Sic Parvis Magna - From small to greatness (Motto given by Queen Elizabeth to Sir Francis Drake (1540-1596) in 1581 for being the first English person to circumnavigate the world)
Sic semper Tyrannus - Thus always to tyrants (Motto of Virginia State )
Sicut in coelo et in terra - As in heaven and earth (Taken from Our Father - Motto of the Spanish Mobile Forces)
Sigillum Militum Xpisti - The Seal of the Soldiers of Christ (This motto was written in Greek and Latin characters in the Templars' rings)
Signum Ostiense - A Sign of Ostia (Pope Alexander IV (1254-1261) motto, according to St. Malachy prophecies - He was Cardinal of Ostia)
Similia Similibus Curantur - Similar cures the similar (Homeopathy motto)
Spem reduxit - Hope reborn (Motto of New Brunswick, Canada)