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Glossary
English
Average: The result obtained by adding two or more amounts together and dividing the total by the number of
amounts (Cambridge University Press, 2004).
Baby Taxi: A three-wheeled vehicle designed for carrying passengers.
Biochemical oxygen demand (BOD): BOD is used to determine the relative oxygen requirements of wastewaters,
effluents and polluted waters. The test measures the molecular oxygen utilized during a specified incubation period
for the biochemical degradation of organic material and the oxygen used to oxidize inorganic material such as
sulfides and ferrous iron. Measurement of oxygen consumed in a 5 days test period (BOD5) is usually used (APHA et
al., 1998).
Chemical oxygen demand (COD): The amount of a specified oxidant that reacts with the sample under controlled
conditions. COD is used as a measurement of pollutants in wastewater and natural waters (APHA et al., 1998).
District: Administrative unit of the government above sub-district. There are 64 districts in Bangladesh.
Escherichia coli (E. coli): A member of the fecal coliform group of bacteria. This organism in water indicates fecal
contamination (APHA et al., 1998).
Eutrophication: The process by which a body of water becomes enriched in dissolved nutrients (as phosphates) that
stimulate the growth of aquatic plant life usually resulting in the depletion of dissolved oxygen (Merriam-Webster,
2005)
Fecal coilform (FC): A group of bacteria that are passed through the fecal excrement of humans, livestock and
wildlife.
Gross domestic product (GDP): An aggregate measure of production equal to the sum of the gross values added
of all resident institutional units engaged in production (plus any taxes, and minus any subsidies, on products not
included in the value of their outputs). The sum of the final uses of goods and services (all uses except intermediate
consumption) measured in purchasers’ prices, less the value of imports of goods and services, or the sum of primary
incomes distributed by resident producer units.
Hydrolysis: A chemical reaction in which one substance reacts with water to produce another (Cambridge University
Press, 2004).
Lipid: A substance such as a fat, oil or wax that dissolves in alcohol but not in water and is an important part of
living cells (Cambridge University Press, 2004).
Median: Median describes the value which is the middle one in a set of values arranged in order of size (Cambridge
University Press, 2004).
Monomer: A molecule that can combine with others to form a polymer (Houghton Mifflin Company, 2000).
pH: A number which shows how strongly acid or alkaline a substance is, in a range from 0 to 14; below pH 6.5 is acid,
above pH 7.5 is alkaline (Cambridge University Press, 2004).
Polymer: A chemical substance consisting of large molecules made from many smaller and simpler molecules
(Cambridge University Press, 2004).
Potassium dichromate method: A method of measuring COD using potassium dichromate (K2Cr2O7). There is
another method of measuring COD using potassium permanganate (KMnO4); the value of COD using potassium
permanganate method is generally smaller than potassium dichromate method (APHA et al., 1998).
Poverty line: An income level that is considered minimally sufficient to sustain a family in terms of food, housing,
clothing, medical needs, and so on.
Standard deviation: A statistic used as a measure of the dispersion or variation in a distribution, equal to the square
root of the arithmetic mean of the squares of the deviations from the arithmetic mean (Houghton Mifflin Company,
2000).
Bangladeshi
Almirah: Drawer or cupboard.
Masjid: Mosque.
Ricksha/rickshaw: A small covered passenger vehicle based on a tricycle.
Thana: Synonymous to sub-district. Bangladesh has 490 thanas. On an average each thana consists of 10-12 unions.
Union is the lowest level administrative unit of Bangladesh and the country is divided in to 4451 unions. Several
villages form a union.
Sources:
APHA, AWWA and WEF (1998): Standard Methods for the Examination of Water and Wastewater, 20th Edition.
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