ridge / rij/ • n. a long narrow hilltop, mountain range, or watershed: the northeast ridge of Everest. ∎  the line or edge formed where the two sloping sides of a roof meet at the top. ∎  Meteorol. an elongated region of high atmospheric pressure. ∎  a narrow raised band running along or across a surface: buff your nails in order to smooth ridges. ∎  a raised strip of arable land, esp. (in medieval open fields) one of a set separated by furrows.• v. [tr.] [often as adj.] (ridged) mark with or form into narrow raised bands: the ridged sand of the beach. ∎  [intr.] (of a surface) form into or rise up as a narrow raised band: the crust of the earth ridged. ∎  form (arable land) into raised strips separated by furrows: a field plowed in narrow stretches that are ridged up slightly.DERIVATIVES: ridg·y adj.

ridge
1. (wedge) An extension of high pressure from an anticyclone into a zone where generally lower pressure prevails.

2. The poleward meanders of the flow of the upper westerly winds over mid-latitudes.

3. (mid-oceanic ridge, oceanic ridge) A long, linear, elevated, volcanic structure that often lies along the middle of the ocean floor. Such ridges tend to occupy central positions because the oceans have formed by the symmetrical spreading of two lithospheric plates from the ridge sites. Oceanic ridges occur in all the Earth's oceans, but may be offset from a central position (e.g. the east Pacific ridge, where one side of the oceanic crust is being consumed along a subduction zone.

4. See ridge-and-ravine topography and ridge and runnel.

ridge.
1. Apex of a pitched roof where the two slopes meet, especially the horizontal edge thus formed, often decorated with a ridgecrest.

2. Structural top of a pitched roof, including the timber, or ridge-piece, against which the upper ends of rafters abut or pitch.

3. Internal apex of a Pointed Gothic vault, often covered by a ridge-rib.

ridge
1. (wedge) An extension of high pressure from an anticyclone into a zone where generally lower pressure prevails.

2. The poleward meanders of the flow of the upper westerly winds over mid latitudes. See also long wave.

3. See MID-OCEAN RIDGE.

4. See RIDGE-AND-RAVINE TOPOGRAPHY; and RIDGE AND RUNNEL.

Ridge / rij/ , Tom (1945– ), U.S. secretary of homeland security 2001–05; full name Thomas Joseph Ridge. The governor of Pennsylvania 1995–2001, he was chosen by President George W. Bush to head the new Office of Homeland Security, a cabinet department created shortly after the terrorist attacks of September 11, 2001.