telephoto lens

Wiktionary

1. n. photography A lens having a long focal length which produces a magnified view of distant objects.
2. n. photography A lens which produces a magnified view of distant objects and which is sufficiently compact to have a physical length shorter than its focal length (as distinct from a long-focus lens).

GNU Webster's 1913

1. n. a special compound camera lens with a long effective focal length but used in a camera with a short focal length, allowing large images to be obtained of distant objects when used in a camera in place of an ordinary lens; -- called also telephotographic lens.

WordNet 3.0

1. n. a camera lens that magnifies the image