Kalman Hardy, 88, a former general in the Hungarian royal army and a retired language professor at Georgetown University, died of cardiac arrest Saturday at a Hospital in Columbia, S.C.

Born in Pecs, Hungary, Dr. Hardy graduated from the Austro-Hungarian Imperial Naval Academy and served in the Austro-Hungarian Navy during World War I. He later joined the Hungarian army.

From 1936 to 1940, he was the Hungarian military attache in Berlin and subsequently served as commander in chief of the Hungarian Army's river fleet.

In 1944, he was arrested and later condemned to death for his part in Hungarian Regent Nicholas Horthy's failed attempt to reach an armistice with Russia.

He was liberated by U.S. troops in Ostermunchen, Germany, in 1945, and served as an expert witness during the Nuremberg war crimes trials.

Dr. Hardy came to this country in 1951 and lived in New York City before moving to the Washington area in 1955. He was a professor of the German and Hungarian languages at Georgetown until his retirement in 1962.

He then taught German at Howard University here and at Gannon College in Erie, Pa., before retiring a second time after the death of his wife, the former Marga Graefl, in 1972.

Dr. Hardy then moved to Columbia, S.C., to live with a daughter, Paula Gorgey, and her family.

Besides Mrs. Gorgey, survivors include two other daughters, Margaret Williams of Washington, and Susan Hardy of San Diego, Calif., a brother, Bela Hardy of Monte Carlo, and four grandchildren.