Acre
A measure of land, 43,560 square feet, regardless of shape. A 209-foot square is 1 acre. An acre is also 160 square poles.

ALTA/ACSM Land Title Survey
A land survey which meets certain detailed specifications intended to address common issues and scope needed by title insurance companies and lenders and others for national commercial deals.  In its simplest form, this is a detailed boundary survey showing title easements and building outlines.  There are several commonly requested additional items in Table A of the specifications document, which is published by the American Land Title Association.

Angle
The difference in direction between two lines.

Base line
A surveyed line established with greater than usual care. A baseline serves as a line of reference for future surveying activities.

Bearing
The direction of a line as expressed with respect to a reference median, for example North or South. Typical bearings are:

North 30° East (30-degrees of angle clockwise from due North),
South 60°05’ West (60-degrees and 5-minutes of angle clockwise from due South)
N23°16’30”W (23-degrees and 16-minutes and 30-seconds of angle counter-clockwise from due North)

Bench Mark
A relatively permanent material object, natural or artificial, whose elevation above an adopted datum, such as sea level, is known.

Boundary Monument
An object placed on or near a boundary line to preserve and identify the location of the boundary line on the ground.

Chain
A unit of length used by surveyors in the 1800’s. The “Gunter’s chain” is 66-feet long and is divided into 100 links each, each 7.92 inches long. A Gunter’s chain is 4 poles in length. Other earlier chains were 33 feet in length. (“Rathbone’s Chain). An “Engineer’s Chin is 100 feet in length. The chain is a convenient length for land measurement because 10 square chains = 1 acre.

Common Law
The body of judicial decisions by appellate courts developed over time. The English common law forms the foundation for the system of law in the United States of America.

Datum
A reference line or plane from which other points or locations are measured.  For example, Mean Sea Level. Note that new datums are adopted periodically as geologists model the earth’s shape and gravitational field.  Examples include: (1) National Geodetic Vertical Datum of 1929, (2) North American [Horizontal] Datum of 1983 and (3) North American Vertical Datum of 1988.

Flood Plain
A low-lying area adjacent to a creek, river or other water of body, which area has been determined to be prone to flooding based on statistical engineering studies.  These flood zones are computed based on certain assumed conditions (for example, a 100-year flood) and commonly have various components (for example, a floodway encroachment area and a flood fringe area).  Each component is subject to a different set of constraints for new development design.

Grantee
A person, to whom property is conveyed by a deed, or to whom property rights are granted by a trust instrument or other document.

Grantor
A person who conveys property by deed, or grants property rights through another document.

Gravity
The physical force created by the mass of the earth, which attracts objects generally toward its center. However gravity may not pull towards the same center point from all places on the earth’s surface due to slight differences in density within the earth.

Link
A unit of linear measure, which is one-hundredth of a chain (7.92 inches) (See also chain)

Metes and Bounds
A method of describing land by measurements (metes) and boundary features (bounds).  This description provides a somewhat detailed narrative of the perimeter of the land tract being described.

Perch
A measure of length equivalent to 1-rod or 1-pole or 16-½ feet.

Pole
A measure of length containing 16.5-feet. Same length as a Rod or Perch.

Rod
A measure of length containing, 16-½ feet. Same length as a Pole or Perch.

Survey, ALTA/ACSM Land Title
A land survey which meets certain detailed specifications intended to address common issues and scope needed by title insurance companies and lenders and others for national commercial deals.  In its simplest form, this is a detailed boundary survey showing title easements and building outlines.  There are several commonly requested additional items in Table A of the specifications document, which is published by the American Land Title Association.

Survey, As-built
A land survey including the boundary of the land parcel plus physical improvements, such as buildings, driveways and other structures, shown within the context of that boundary.

Surveying, land
Land surveying is the art and science of locating features on the earth’s surface. Specifically a “Boundary Survey” reflects the analysis of record documents and field measurements to determine the location shape size and area of land parcels, usually presented graphically as a map.