San Antonio is sometimes called “S.A.” or “SA” or “SA Town” (or hyphenated as “SA-Town”). It’s pronounced like “say town,” not the two letters like in “essay town.” The context of the speech or writing should be clear because “SA” could also stand for “South America” or “South Africa.”
     
Dallas has long been known as “Big D,” but hip-hop slang in the 1990s brought “D-Town” and “H-Town” (Houston). “SA Town” joined the list a bit later in the 1990s.
 
 
Wikipedia: List of city nicknames in Texas
San Antonio
Alamo City
Military City U.S.A.
Mission City
River City
San Antone
San Anto
SA Town
Americas City (due to the Tower Of Americas, tallest observation tower in America until 1996)
San An
 
Wikipedia: San Antonio, Texas
San Antonio (pronounced /ˌsænænˈtoʊnioʊ/) is the second-largest city in the state of Texas and the seventh-largest in the United States of America. Located in the northern part of South Texas, the city is a cultural gateway into the American Southwest. San Antonio is the seat of Bexar County with a population just under 1.3 million as of the 2006 U.S. Census estimate, as well as the 4th fastest growing large city in the nation from 2000-2006 in terms of percentage. Its metropolitan area has a population of over 1.9 million and is the 29th-largest metropolitan area in the U.S.
   
San Antonio was named for the Italian Saint Anthony of Padua, whose feast day it was (June 13) when a Spanish expedition stopped in the area in 1691. The city has a strong military presence—it is home to Fort Sam Houston, Lackland Air Force Base, Randolph Air Force Base, and Brooks City-Base, with Camp Bullis and Camp Stanley right outside the city. San Antonio is home to the South Texas Medical Center, the only medical research and care provider in the South Texas region.
   
Famous for its River Walk, the Alamo, Tejano culture, and home to the SeaWorld San Antonio and Six Flags Fiesta Texas theme parks, the city is visited by 20 million tourists per year. San Antonio is also home to the first museum of modern art in Texas—the Marion Koogler McNay Art Museum, as well as one of the most successful National Basketball Association teams in league history, the San Antonio Spurs. 
 
Urban Dictionary
1. sa-town
San Antonio, Texas aka San Anoton aka Satown
lil sin, lil ken, texas made boiz are from that sa-town straight holdin down
by long john Jun 30, 2003
 
2. sa-town
Where the Spurs are from.
Go Spurs Go.
The Spurs are from sa-town
by MAGIC Oct 6, 2004
 
3. sa-town 
San antonio.The best city in the world.Where the finest and best of beautiful women rome.sa-town 4 life.
Damn that honey fine,yeah she must be from san antonio.
by bonemaster your chicks house. Apr 29, 2005
 
4. sa-town
its San Antone not San Anaton.
people been callin San Antonio Sa-Town and San Antone for a while. Dont know how it started just always called my city that.
rollin on chrome, out tha san antone
nawfside were i rome, freestyle off my dome
by Anthony Jul 21, 2004
 
5. SA-Town
Nickname for San Antonio, Texas. Name is referenced to A-Town. Other towns in the state of Texas have “A-Town” nicknames, such as Houston, H-Town.
98.5 is the best radio station up in the 210, SA-Town!
by Ellie Rae San antonio, Texas May 11, 2007
 
Google Groups: rec.sport.rugby
Newsgroups: rec.sport.rugby
From: .(JavaScript must be enabled to view this email address) (Larry Romo)
Date: 1995/06/02
Subject: Recruiting for Alamo City RFC
 
Anyone wanting to play in beautiful San Antonio, Texas, the Alamo City RFC is always looking for good players, social members and friends of rugby.  We are especially looking for a prop and scrum half for next year but are always looking at all positions.  SA is a town of one million folks and there are many jobs to be had.
   
Google Groups: rec.music.hip-hop
Newsgroups: rec.music.hip-hop
From: .(JavaScript must be enabled to view this email address)
Date: 1997/07/29
Subject: Re: Why hip-hop is making a comback in ‘97
   
But in every song from said artist, they big up where they are from With the K-otix and Example they talk about houston, and the stuff we go through.  Shabbaz 3 Epatomed hits up dallas, 3-D has a lot to say about SA town. 
 
Google Groups: rec.music.hip-hop
Newsgroups: rec.music.hip-hop, alt.rap
From: “Reginald . Williams”
Date: 1997/10/09
Subject: Down South Hip Hop
 
let me know of any tight artists from Austin, we mostly get artists from Houston down n Sa Town.
         
MySA.com
Gunfire from Cadillac ends young cyclist’s life (June 13, 1998)
Nathalie Trepanier EXPRESS-NEWS STAFF WRITER   San Antonio Express-News (TX)
Metro and State News Page 01B (466 Words)
 
Cyrus Bates moved to San Antonio from Corpus Christi last year because he wanted to stay out of trouble, his mother recalled Friday after she cleaned the blood of her only son from the street corner where he was gunned down, just two blocks from home. Bates, 17, was slain Thursday night in a drive-by shooting while riding his bike along the 400 block of Natalen.
(...)
Police said a mural of San Antonio bearing the words “Down with SA Town” is painted on the back of the suspects’ car.
   
MySA.com
Cancer lives on S.A. town hall meetings to assess advances, ‘explosion of new knowledge’ against stubborn disease (August 17, 1998)
Marina Pisano Express-News Staff Writer   San Antonio Express-News
S.A. Life Page 1D (1170 Words)
 
Twenty-seven years after President Nixon declared a nationwide War on Cancer, calling for a cure by 1980, cancer continues to kill about 1,500 Americans a day. The cure for which stricken families long for remains elusive. 
 
Google Groups: alt.rap
Newsgroups: alt.rap
From: .(JavaScript must be enabled to view this email address) (True080979)
Date: 1999/06/01
Subject: Re: Questions
 
good luck, and if you’re ever in SA town let me know and perhaps we can collab…
   
Google Groups: alt.rap
Newsgroups: alt.rap
From: .(JavaScript must be enabled to view this email address) (True080979)
Date: 1999/11/08
Subject: Re: 10 BEST MC’s EVER - continuing the arguement… 
 
Everyone in SA Town raps the same,...
   
Google Groups: alt.rap
Newsgroups: alt.rap
From: Rodrigo

Date: Sun, 12 May 2002 10:33:49 -0500
Local: Sun, May 12 2002 10:33 am
Subject: Re: Sports
   
oh yeah, another spurs fan… sure, they seem to choke here abd there, but its time to win that championship withou an asterick this time. Sa Town fo life…
 
MySA.com: Roy Bragg
November 06, 2007
Satan Tonio welcomes you
Welcome to the Alamo City, also known as by a dozen or so obscure nicknames.
(...)
Very unoriginal minds came up with SA Town (pronounced Say-town). That’s just lazy, since there’s already D-Town for Detroit and C-Town for Cleveland. What’s next? S-Town for Seguin? F-ville for Floresville?
 
If you use the first letter of your city’s name and stick it in front of “town,” then you’re just mailing it in.
(...)
“San AN” and “SA” are likely the best ones, since they were probably created by locals. They’re easy to remember and they aren’t intended to make a statement or evoke imagery. They are truncated versions of the city’s name. Busy people — with active lives, real jobs and dynamic families — probably came up with “San An” and “SA,” so that makes those names the best ones.