Definitions for "Base line"
(1) A survey line used in the government survey to establish township lines. The base line runs east and west through a principal meridian (line running north and south). (2) A horizontal elevation line used as the centerline in a survey for a highway route.
(1) A surveyed line of great accuracy which serves as the basis for measurement of other lines or of the angles between them. (2) In a land survey system an East-West line passing through the origin from which township, section, and quarter-section corners are established.
The base line of a projection refers to the period of population change that is being extrapolated.
The normative (i.e., typical) state of an individual or of an investigative parameter prior to an experimental manipulation.
Keywords:  see
See baseline.