The Ethiopian-born Gabriel died Monday of sudden cardiac arrest at Kaiser Permanente Panorama City Medical Center, said university spokeswoman Teri Bond.
"He was a brilliant, gracious, elegant and generous man," Teri Schwartz, dean of the School of Theater, Film and Television, said in a statement Wednesday. "Teshome was a consummate professional and a truly beloved faculty member at TFT. He will be greatly missed by all of us."
Gabriel, who began as a lecturer at UCLA in 1974 and received his doctorate in film and television studies there before becoming an assistant professor in 1981, was the author of the 1982 book "Third Cinema in the Third World: The Aesthetics of Liberation."
Vinay Lal, an associate professor of history and Asian American studies at UCLA, said Gabriel was "one of the first scholars to theorize in a critical fashion about Third World cinema."
"He is a principal exponent of the idea of Third Cinema," Lal, who is on leave, said via e-mail from India. "He saw such a third cinema as a guardian of popular memory and as a source of emancipation for formerly subjugated peoples.
"While Third Cinema would develop its own conventions of narrative and style, its aesthetic had to be tied to a politics of social action. Teshome was very attentive, as a film scholar must be, to cinematic styles and conventions; but he kept very close to his heart the idea that Third World cinemas had to be true to the cultures, traditions and forms of storytelling found in those societies."
Gabriel co-edited the 1993 book "Otherness and the Media: The Ethnography of the Imagined and the Imaged" and most recently wrote the book "Third Cinema: Exploration of Nomadic Aesthetics & Narrative Communities."
His many other accomplishments included serving as editor in chief of "Emergences: Journal for the Study of Media and Composite Cultures." He also was founder and an editorial board member of Tuwaf (Light), an Ethiopian Fine Arts Journal in Amharic, from 1987 to 1991.
In his later years, Lal said, Gabriel "wrote on such things as the relationship of the Web to weaving, the idea of the nomadic (and the transgressive), and the relationship between the built form and ruins.
"He was a rare thinker, interested in allowing ideas a free play, and he never ceased to explore new forms of media as well as developments in cinema."
Gabriel was born Sept. 24, 1939, in the small town of Ticho, Ethiopia, and came to the United States in 1962.
He received a bachelor's degree in political science from the University of Utah in 1967, followed by a master's of education in educational media two years later. At UCLA, he earned a master's degree in theater arts (film/television) in 1976 and his doctorate in film and television studies in 1979.
He is survived by his wife, Maaza Woldemusie; daughter, Mediget; and son, Tsegaye.
A memorial service is planned for 3 p.m. Saturday at Forest Lawn Hollywood Hills, 6300 Forest Lawn Drive, Los Angeles.