Which of these is not a nickname for Seattle?

Seattle does not have the nickname of "Happy City".

Seattle is a seaport city on the west coast of the United States. It is the seat of King County, Washington. With an estimated 704,352 residents as of 2016, Seattle is the largest city in both the state of Washington and the Pacific Northwest region of North America. The city is situated on an isthmus between Puget Sound (an inlet of the Pacific Ocean) and Lake Washington, about 100 miles (160 km) south of the Canada–United States border. A major gateway for trade with Asia, Seattle is the fourth-largest port in North America in terms of container handling as of 2015.

From 1869 until 1982, Seattle was known as the "Queen City". Seattle's current official nickname is the "Emerald City", the result of a contest held in 1981; the reference is to the lush evergreen forests of the area. Seattle is also referred to informally as the "Gateway to Alaska" for being the nearest major city in the contiguous U.S. to Alaska, "Rain City" for its frequent cloudy and rainy weather, and "Jet City" from the local influence of Boeing. The city has two official slogans or mottos: "The City of Flowers", meant to encourage the planting of flowers to beautify the city, and "The City of Goodwill", adopted prior to the 1990 Goodwill Games. Seattle residents are known as Seattleites.