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Rosetta

(Encyclopedia)Rosetta räshēdˈ [key], city (1986 pop. 51,789), N Egypt, in the Nile River delta. The city once dominated the region's rice market; rice milling and fish processing are the main industries of moder...

defoliant

(Encyclopedia)defoliant, any one of several chemical compounds that, when applied to plants, can alter their metabolism, causing the leaves to drop off. In agriculture defoliants are used to eliminate the leaves of...

eutrophication

(Encyclopedia)eutrophication yo͞otrōˌfĭkāˈshən [key], aging of a lake by biological enrichment of its water. In a young lake the water is cold and clear, supporting little life. With time, streams draining i...

trapping

(Encyclopedia)trapping, most broadly, the use of mechanical or deceptive devices to capture, kill, or injure animals. It may be applied to the practice of using birdlime to capture birds, lobster pots to trap lobst...

Bakassi

(Encyclopedia)Bakassi bäkäˈsē [key], peninsula, c.400 sq mi (1,000 sq km), E Cameroon, on the Cameroon-Nigeria border, at the SE end of the Gulf of Guinea. The swampy peninsula and associated small islands are ...

porpoise

(Encyclopedia)porpoise, small whale of the family Phocaenidae, allied to the dolphin. Porpoises, like other whales, are mammals; they are warm-blooded, breathe air, and give birth to live young, which they suckle w...

fossa

(Encyclopedia)fossa, carnivorous mammal, Cryptoprocta ferox, of Madagascar. The island's largest carnivore, the fossa resembles a puma in appearance and has semiretractable claws, but it is most closely related to ...

Freetown

(Encyclopedia)Freetown, city (1995 est. pop. 519,500), capital of Sierra Leone, W Sierra Leone, a port on the Atlantic Ocean. Located on the Sierra Leone peninsula, Freetown is the nation's administrative, communic...

echo sounder

(Encyclopedia)echo sounder, an older instrumentation system for indirectly determining ocean floor depth. Echo sounding is based on the principle that water is an excellent medium for the transmission of sound wave...

gull

(Encyclopedia)gull, common name for an aquatic bird of the family Laridae, which also includes the tern and the jaeger. It is found near all oceans and many inland waters. Gulls are larger and bulkier than terns, a...