"ascertaining the position of a ship by measurement of the distance run," 1610s, might be from nautical abbreviation ded. ("deduced") in log books, but it also fits dead (adj.) in [..]

method of navigation based on past position to determine a vessel's current position.

See deductive reckoning 

Estimating a ship’s position by working out speed and direction of travel. Not as accurate as using astronomical methods.

Dead reckoning is the ability possessed, in varying degrees, by both animals and humans to be mentally aware of a starting point at any location and be able to return to the starting location. Animals [..]

Early navigators used dead reckoning to go from port to port, or across a lake. First they plotted their location based on the positions of the stars, moon, and sun, then determined their destination [..]

A calculation of the ship’s place without any observation of the heavenly bodies. A guess made by consulting the log, the time, the direction, the wind, and so on. Such a calculation may suff [..]

The process of determining a vessel's approximate position by applying from its last known position a vector or a series of consecutive vectors representing the run that has since been made, usin [..]

also Ded Reckoning.  Sometimes believed to be an abbreviation of Deduced Reckoning

A navigation technique based on plotting courses and making calculations based on aircraft performance data and forecast winds aloft.

A method of estimating position based on starting position, speed, and elapsed time.

A method of navigation based on basic information (barometric altitude, magnetic heading, airspeed, wind conditions) from best available source; sometimes short for air data dead reckoning;

The process of determining a vessel's position using only knowledge of a point of departure, vessel's speed, elapsed time and course steered. Originally, dead was spelled "ded" for [..]

determining a position by plotting courses and speeds from a known position.

Calculation of a ship's position by consideration of distance logged, courses steered and estimated leeway. Some­times said to be corruption of 'deduced reckoning'; but this is very deb [..]

A plot of courses steered and distances traveled through the water.

The process of plotting a theoretical position or future position based on advancing from a known position using speed, time, and course, without aid of objects on land, of sights, etc. Term comes fro [..]

 For many years, the practice of keeping a log based on estimated speed was called 'deduced' reckoning. Over time, this turned into dead reckoning. Dead reckoning is the process by which the [..]

  This navigation term was originally spelled "ded" (the abbreviation for deduced) reckoning. An unscholarly British shipmaster thought the "a" had been omitted, so [..]

navigator's estimate of the position of the ship from the course steered and the distance run. Short for "deductive reckoning." Not always accurate, due to the effects of wind, [..]

A calculation of determining position by using course speed last known position

calculating the position of a vessel from the course steered and the distance run

A method of determining position by making an educated guess based on last known position, speed and currents

The process of plotting a theoretical position or future position based on advancing from a known position using speed, time, and course, without aid of objects on land, of sights, etc. Term comes fro [..]

Determining the position of a vessel by adding to last fix the vessel’s surface course and speed for a given time.

(also ded (for deduced) reckoning) is the process of calculating one's current position by using a previously determined position, and a known (estimated) speed and heading.

A method of calculating a UAV’s position by using a previously known position, and advancing it based upon estimates of speed over time and course.

The estimating or determining of position by advancing an earlier known position by the application of direction, time and speed data.

The process of estimating one’s current position based upon a previously determined position, or fix, and advancing that position based upon known speed, elapsed time, and course.

You reckon correctly, or you are.

A method of navigation based on basic information (barometric altitude, magnetic heading, airspeed, wind conditions) from best available source; sometimes short for air data dead reckoning;

Dead reckoning, as applied to flying, is the navigation of an airplane solely by means of computations based on airspeed, course, heading, wind direction, and speed, groundspeed, and elapsed time.

An unclever contraction of 'deductive reckoning,' which uses speed and direction together with elapsed time to estimate one's present whereabouts from some previously known position. In aviation, the procedure is especially prone to errors, primarily because of winds, but it's anything but "dead." 

You reckon correctly, or you are.

This is a formula to determine where other players and objects are by calculating their positions based on the velocity and last location received. This information will be replaced when other players change velocity and send their new velocity.

A way of figuring your position based upon the influence of such things as currents and wind upon your projected course and anticipated speed.