Vacaville (văk`əvĭl, vä`–), city (1990 pop. 71,479), Solano co., central Calif. about 30 mi (48 km) from Sacramento, in a farm and orchard area; inc. 1892. Sunflower and safflower oils are produced and fruits and vegetables are canned. Manufactures include industrial machinery, aluminum products, mattresses, and metal plate. Vacaville grew tremendously in size as the central California area boomed in the late 20th cent. Travis Air Force Base and Hospital are to the south.