The term 'Quaker St.' is a reference to the Quaker State, which is the nickname for the U.S. state of Pennsylvania. The crossword solution for this term is 'PENNA, ' which is the abbreviation for Pennsylvania. Quakers are members of the Religious Society of Friends, a Christian denomination founded in England in the 17th century. Pennsylvania was founded by William Penn, a Quaker, in 1681 and was the first colony to grant religious freedom to all faiths.