The line traced on amplitude- modulated indicators which corresponds to the power level of the weakest echo detected by the radar; it is retraced with every pulse transmitted by the radar but appears as a nearly continuous display on the scope.

1. A surveyed line, established with more than usual care, to which surveys are referred for coordination and correlation.

2. A cardinal line extending east and west along the astronomic parallel passing through the initial point, along which standard township, section, and quarter-section corners are established.

The bottom alignment of upper-case letters in a font.

The geodesic line joining the two stations between which electrical phase or time is compared in determining navigational coordinates.

A line drawn in the graphical representation of a varying physical quantity, such as a voltage or current, to indicate a reference value, such as the voltage value of a bias.