(informal, US) The cadets of the United States Military Academy.

To behave in a proper and lawful manner; to obey the rules and expectations of society. / Used other than figuratively or idiomatically: see walk, straight, line.

(computing) A user interface in which the user interacts with the computer through lines of text instead of graphical images.

(ice hockey) A pass across two of the three lines dividing the rink, the center red line and the two blue lines. Under some rules such a pass is illegal.

(physics) The jagged line, on a chart showing the number of protons and neutrons of all known isotopes, beyond which neutron-rich nuclei are unstable and emit neutrons.

(mathematics) A line on a scatter plot that best defines or expresses the trend shown in the plotted points. It is chosen so that the sum of the squares of the distances from the points to the line is a minimum. It also illustrates the correlation (positive, negative, or zero correlation) between the plotted variables.

(idiomatic) A clear-cut, easy to make a decision. / (law) A clearly defined rule or standard, composed of objective factors, which leaves little or no room for varying interpretation.

(idiomatic, vulgar) To take a big risk.

Overhead transmission line from the power station to a transmission substation.

simple past tense and past participle of line up one's ducks