What is submarine growler?

The USS Growler (SSG-577) was a George Washington-class, nuclear-powered guided missile submarine in the service of the United States Navy. She was launched in 1958 and served until 1964, participating in various national security missions during the Cold War. One of her notable accomplishments was becoming the first-ever submarine to launch a Regulus cruise missile from beneath the water's surface. The Growler is currently on display at the Intrepid Sea, Air & Space Museum in New York City, where visitors can tour the submarine and learn about the history of submarine warfare.