(chiefly Britain) An at-grade crossing between a railway line and an ordinary road, with rails and road at the same level.

(chemistry) The energy level of the electrons (core electrons) occupying the completely filled shells under the valence shell.

relatively unimportant / not intense / (computing) of, or relating to a program, or to code in which each statement corresponds to a single machine instruction / detailed

Highest. / Best. / (Internet) Applied to domains at the highest level, such as .uk covering all sites for the United Kingdom.

(programming) read-eval-print loop

(transitive, literally and figuratively) To raise to the same level or status; to improve so as to make as good as others.

(idiomatic) Sensible; rational; possessing sound judgment.

The level of a body of water, especially when measured above a datum line. / The level of the water table below ground. / The waterline of a ship.

(tool) A tool employing a chamber with a colored liquid (usually alcohol, hence spirit) and an air bubble, used to determine a horizontal or vertical reference line.

(rail transport) An at-grade junction between two crossing railroad tracks.