Peter Morton Day (August 1, 1914 – May 5, 1984) was a lay journalist and ecumenical leader in the Episcopal Church in the United States in the twentieth century.
Born in East Chicago, Indiana, he was a graduate of Dartmouth College (cum laude 1935).
Day was appointed first national ecumenical officer of the Episcopal Church by Presiding Bishop Arthur C. Lichtenberger in 1964, serving on dialogue committees with Lutheran, Roman Catholic, and other Christian bodies in North America as well as with the Russian Orthodox Church.
Day died in Milwaukee after a prolonged struggle with Alzheimer's Disease.
This article about a United States journalist born in the 1910s is a stub.