Sk

Skeletal Density
The ratio of the mass of discrete pieces of solid material to the sum of the volumes of: the solid material in the pieces and closed or blind pores within the pieces.
Skeletal Volume
The sum of the volumes of the solid material and closed (or blind) pores within the pieces.
Skeleton Division
A long division in which most or all of the digits have been replaced by asterisks to form a cryptarithm.
Skew
An expression of the so-called "third moment".
Skew Lines
Two lines are skew if they are not contained in the same plane.
Skewed Distribution
A distribution that is not symmetrical.
Skewness
Skewness defines the degree of asymmetry of the distribution around its central value.
Skin Effect
In the case of high frequency signals, electrons are only conducted on the outer surface, or skin, of a conductor.
Skin Friction
This is drag due to the surface texture and area.
Skin Temperature
The outer surface temperature of a body.
Skip Distance
The distance from a transmitter to the point where the sky wave is first returned to earth.
Skip Zone
A zone of silence between the point where the ground wave becomes too weak for reception and the sky wave is first returned to earth.
Skirt
The part of the piston below the piston-ring grooves. Designed to counter the lateral force from the connecting rod and guide the piston within the liner.
Sky Cover
The amount of the celestial dome that is hidden by clouds or obscurations.
Sky Wave
The space-wave component of a radio transmission that reaches the receiver by reflection from the ionosphere.
Sky Waves
Radio waves reflected back to earth from the ionosphere.
Skylight
An opening in a roof to admit light.