Definição: A depression caused by erosion by water or ice. Low-lying land bordered by higher ground; especially elongate, relatively large gently sloping depressions of the Earth's surface, commonly situated between two mountains or between ranges of hills or mountains, and often containing a stream with an outlet.
Definição: Any of various immature insects; especially: a larva of an insect (as a grasshopper, true bug, or mayfly) with incomplete metamorphosis that differs from the imago especially in size and in its incompletely developed wings and genitalia.