Mr. Green, who taught at the Corcoran for 40 years before retiring in 2009, was influenced by the Washington Color School that emphasized abstract, geometric paintings in bright colors.
He is perhaps best known for his large paintings of colorful “glyphs” — big, curving, figures that resemble letters from a mysterious alphabet. His paint-spattered home studio was filled with them, and the American University Museum hosted an exhibition of Mr. Green’s work last year.
In 1988, former Washington Post art critic Paul Richard described an enigmatic Green painting as “like a comic strip for Martians,” but with understanding “just around the corner . . . one train of thought away.”
“Green is an original,” Richard wrote. “If the word ‘abstract’ applies, he is one of the most interesting abstract painters in this town.”
Mr. Green’s work has been exhibited at the Corcoran and in New York at the trend-setting Whitney Biennial at the Whitney Museum of American Art and at the Guggenheim Museum.
While other local artists of his day moved to New York, he preferred to work in his rustic studio in Cabin John.
Thomas Patrick Green Jr. was born May 27, 1942, in Newark, N.J., the oldest of four children of a printer who moved his family to suburban Maryland when he got a job at the Government Printing Office in Washington.
Mr. Green graduated in 1960 from Archbishop Carroll High School in Northeast Washington, where, he wrote later, he learned artistic self control and an understanding of form in a mechanical drawing class.
At the University of Maryland, he earned a bachelor’s degree in fine arts in 1967 and a master’s degree in painting in 1969 — but not before flunking out “a couple of times,” he said in a 1989 article inThe Washington Post Magazine.
He told The Post last year that he was caught up in the social and artistic upheaval of those times. “It was pre-hippie,” he said. “I was kind of like a beatnik.”
There was much experimentation.
He once sprinkled gunpowder on paper and set it afire, to get a starting point for a painting. It was tricky, he said: “You have to be careful not to use too much.”
He drew with mustard and with pokeberry ink.
“I was trying everything then,” he said. “That was the kind of thing that was in the air.”
He once set up an art installation that included sharpened tree branches he had charred with a blowtorch.
In 1969, when he was first offered a chance to show his work at a gallery in Georgetown, he recalled later, he began hyperventilating and had to be taken to the hospital.
“I thought I’d had a heart attack,” he recounted in the Post Magazine. But he realized, “Yeah, I’m an artist. This is serious. I’m on my way now.”
Last year, he said that finishing a painting often was an artist’s biggest problem.
“It’s easy, basically, to start a painting,” he said. “To know when to stop is infinitely harder. You’ve got to decide: Is this complete? Does it have everything that I wanted from it?”
Mr. Green’s first marriage, to artist Cynthia Bickley, ended in divorce. He and his wife, the former Linda DeMarinis, were married in 1990, although they had been living together for almost 20 years before that.
Besides his wife, survivors include a stepdaughter, Kathryn Wichmann of Washington; and two sisters.
Last year, Mr. Green spoke publicly about his illness, a terminal neurological disease that is named for the baseball great whose life it took in 1941. It usually runs its course in two to five years.
“In some ways I’m relieved,” Mr. Green said of his prognosis. “Because I don’t want to grow old and infirm. . . . I see this as an opportunity to die, which I don’t mind.”