a. 1. Being in a condition or situation where life or serious harm is possible; in danger; at risk. [ PJC ]

2. Small in numbers, with significant possibility of extinction; -- of species. [ PJC ]

n. sing. & pl. A species of plant or animal that has declined in numbers to a point where further irreversible decline and extinction{ 3 } has a significant chance. Lists of endangered species are maintained by government agencies, and in many cases the killing of such species or destruction of their habitat is prohibited by law. In the U. S. in recent years, development of certain tracts of land has been prohibited due to the likelihood that it will cause a reduction in the numbers of an endangered species. In some cases environmental organizations have initiated litigation to cause the courts to rule that a certain development plan is illegal due to a threat to an endangered species. Laws protecting endangered species have become in some cases a contentious political issue. [ PJC ]

‖n. [ L., touch me not. ] 1. (Bot.) (a) Any plant of a genus of herbs (Impatiens) having capsules which, if touched when ripe, discharge their seeds. -- See Impatiens. (b) The squirting cucumber. See under Cucumber. [ 1913 Webster ]

2. (Med.) A name formerly applied to several varieties of ulcerous cutaneous diseases, but now restricted to Lupus exedens, an ulcerative affection of the nose. [ 1913 Webster ]