What is "hop bottom"

Population (2000): 333
Housing Units (2000): 140
Land area (2000): 0.602035 sq. miles (1.559264 sq. km)
Water area (2000): 0.000919 sq. miles (0.002381 sq. km)
Total area (2000): 0.602954 sq. miles (1.561645 sq. km)
FIPS code: 35624
Located within: Pennsylvania (PA), FIPS 42
Location: 41.704931 N, 75.765667 W
ZIP Codes (1990): 18824
Note: some ZIP codes may be omitted esp. for suburbs.
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