cover:

1- Vegetation used by wildlife for protection from predators, or to mitigate weather conditions, or to reproduce. May also refer to the protection of the soil and the shading provided to herbs and forbs by vegetation.

www.or.blm.gov/roseburg/ROD_RMP/roseburg/glossary.

2- (a) Any plant that intercepts rain drops before they reach the soil or that holds soil in place. (b) A hiding place or vegetative shelter for wildlife from predators or inclement weather.

forestry.about.com/library/glossary/blforglc.htm

3- The area of ground covered by the vertical projection of the aerial parts of plants of one or more species. (FGDC, 1997).

biology.usgs.gov/npsveg/glossary.html

4- Any feature that conceals wildlife or fish. Cover may be dead or live vegetation, boulders, or undercut stream banks. Animals use cover to escape from predators, rest, or feed.

www.reo.gov/general/definitions_a-m.htm

5- Any of several types of cover that wildlife require to stay alive and reproduce, including to stay warm or cool (thermal cover), to escape from enemies (escape cover), or to hide from perceived danger (hiding cover). Many animals will more readily cross an open area if hiding cover is available nearby to enable them to survey for danger before crossing. Cover is usually vegetation, but it can be structural such as boulders or other topographical features.

www.wildlifecrossings.info/glossary.htm