“Pasadenan” is the name of an inhabitant of Pasadena, Texas. The name “Pasadenan” has been cited in print since at least 1951.
 
The yearbook of Pasadena Senior High School has been called The Pasadenian since 1939, but “Pasadenian” is otherwise rarely used.
 
   
Wikipedia: Pasadena, Texas
Pasadena ( /ˌpæsəˈdiːnə/) is a city in the U.S. state of Texas within the Houston–Sugar Land–Baytown metropolitan area. It is the second-largest city in Harris County, 17th-largest in Texas, and 162nd largest in the United States. The area was founded in 1893 by John H. Burnett of Galveston. Burnett, the founder, named the area after Pasadena, California because of the perceived lush vegetation.
 
As of the 2010 U.S. Census, the city’s population was 149,043. The Pasadena Volunteer Fire Department is the largest all volunteer municipal fire department in the United States.
   
Free Merriam-Webster Dictionary
Pas·a·de·na geographical name \ˌpa-sə-ˈdē-nə\
Definition of PASADENA
1city SW California just NE of Los Angeles pop 133,936
2city SE Texas E of Houston pop 141,674
— Pas·a·de·nan \-nən\ noun
 
OCLC WorldCat record
Pasadenian.
Author: Pasadena Senior High School.
Publisher: Pasadena, TX. : Pasadena High School, 1939-
Edition/Format:  Book : English
 
5 July 1951, Baytown (TX) Sun, “Felton’s Nine To Entertain Pasadena Club,” pg. 27, col. 3:
Pasadena has won two and lost one. The Pasadenans have two more games to play, while Baytown closes conference play against Channelview at 4 p.m. Sunday in Channelview.
 
7 June 1961, Baytown (TX) Sun, pg. 1, col. 6:
Trinity Bay Search
On For Pasadenan
A search for a Pasadena man believed to have fallen from his boat into Trinity Bay about 7 p.m. Thursday is still underway by Baytown and Anahuac emergency corps.
 
30 December 1962, Baytown (TX) Sun, pg. 2, col. 6:
Rabid Dog Bites
Three Pasadenans
 
24 July 1969, Dallas (TX) Morning News, pg. 14A, col. 3:
Pasadenan Elected
ARLINGTON, Va. (AP)—Lee GIlbert of Pasadena, Texas, was among 13 vice-presidents elected at the annual convention of the International Conerence of Police Associations Tuesday.
 
Explore Pasadena-Baytown, Texas
Volunteer Pasadena
Posted Date: 5/17/2011
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Background
Volunteer Pasadena was initiated by Mayor John Manlove. During his mayoral campaign the mayor was impressed by the willingness of citizens to volunteer due to their love of Pasadena.  This solidified his belief in the generosity and caring of the citizens of Pasadena.  Mayor Manlove knew that if a volunteer program was created Pasadenans would be willing to share their time and talents with others.