Giffords was on hand for the ceremony for the Independence-variant littoral combat ship -- the Navy's fifth -- as Navy Secretary Ray Mabus lauded her for her actions in Congress supporting the military.
"You make this occasion special by your presence," Mabus told Giffords, adding, "The name this ship bears, and the story represented by that name, will inspire all those who come in contact with her."
He said Giffords exemplifies the Navy's motto of "Semper Fortis" -- "Always Courageous."
The ship, which will be built in Mobile, Ala., by Austal USA, will be 419 feet long, have a waterline beam of 103 feet, displace about 3,000 tons and travel in excess of 40 knots.
Earlier in the day, President Barack Obama signed into law the last piece of legislation proposed by Giffords, the Ultralight Aircraft Smuggling Prevention Act of 2012, which expands police authority to combat drug trafficking on the nation's borders.
Giffords was shot in the head in January 2011 during a meeting with constituents outside a Tucson grocery store. Six other people were killed and a dozen injured. She resigned from Congress last month to concentrate on her recovery.