1. The unexposed, rough masonry surface of a wall that is faced with finer work.

2. The earth backfill of a retaining wall.

Flexible material, usually cellulose acetate or polyester, used on magnetic tape as the carrier for the oxide coating.

See <<backing strip>>

1. Internationally, a change in wind direction in a counterclockwise sense (for example, south to east) in either hemisphere of the earth.

2. In United States usage, a change in wind direction in a counterclockwise sense in the Northern Hemisphere, clockwise in the Southern Hemisphere.

Timbers across the top of a level, supported in notches cut in the rock.