The depth to which the water present in the soil is expected to freeze in winter. / The depth to which the water present in the soil is actually frozen in a given place at a given point in time.

A cut through forest cleared to permit seismic survey.

A faunal boundary line that separates the ecozones of Asia and Wallacea, a transitional zone between Asia and Australia.

(anatomy) The line that divides the upper two thirds of the anal canal from the lower third. Developmentally, it represents the hindgut-proctodeum junction.

(meteorology) An imaginary line across a continent that separates moist air from an eastern body of water and dry desert air from the west.

plural of line number

(computing) The sequential number indicating a particular line of text in a text file.

a line drawn (on a map) in a maritime area which marks the maritime boundary between two countries.

A navigator's observation of the Sun to determine latitude.

(anatomy) A line from the root of the nose to the lambda.