The Collaborative International Dictionary of English v.0.48:

napa \napa\ n.
   A plant (Brassica rapa pekinensis) with an elongated
   celerylike head of broadstalked leaves used as a vegetable in
   east Asia; called also Chinese cabbage.

   Syn: Chinese cabbage, celery cabbage, pe-tsai, Brassica
        rapa pekinensis.
        [WordNet 1.5]

WordNet (r) 3.0 (2006):

napa
    n 1: plant with an elongated head of broad stalked leaves
         resembling celery; used as a vegetable in east Asia [syn:
         Chinese cabbage, celery cabbage, napa, pe-tsai,
         Brassica rapa pekinensis]

U.S. Gazetteer Counties (2000):

Napa -- U.S. County in California
   Population (2000):    124279
   Housing Units (2000): 48554
   Land area (2000):     753.733557 sq. miles (1952.160868 sq. km)
   Water area (2000):    34.534379 sq. miles (89.443626 sq. km)
   Total area (2000):    788.267936 sq. miles (2041.604494 sq. km)
   Located within:       California (CA), FIPS 06
   Location:             38.353762 N, 122.332133 W
   Headwords:
    Napa
    Napa, CA
    Napa County
    Napa County, CA


U.S. Gazetteer Places (2000):

Napa, CA -- U.S. city in California
   Population (2000):    72585
   Housing Units (2000): 27776
   Land area (2000):     17.697440 sq. miles (45.836158 sq. km)
   Water area (2000):    0.091795 sq. miles (0.237748 sq. km)
   Total area (2000):    17.789235 sq. miles (46.073906 sq. km)
   FIPS code:            50258
   Located within:       California (CA), FIPS 06
   Location:             38.304764 N, 122.298885 W
   ZIP Codes (1990):     94559
   Note: some ZIP codes may be omitted esp. for suburbs.
   Headwords:
    Napa, CA
    Napa