"ded reckoning"?

Posted by Lawrence Wildman on July 29, 2005

In the explanation for the origin of the phrase "dead ringer" it is noted that :

"Dead, in the sense of lifeless, is so commonly used that we tend to ignore its other meanings. The meaning that's relevant here is exact or precise. This is also the sense it is used in the term 'dead reckoning'."

I was given to understand that the orinal phrase was rather "ded reckoning" which was an abbreviated form of "deduced rekconing" a nautical term for estimating position by use of speed, elapsed time and direction to "deduce" a vessel's position. I cannot remember the source; am I totally wrong about this origin?

• "ded reckoning"? ESC 29/July/05
  • Dead reckoning R. Berg 30/July/05
    • Dead reckoning Donald C Cook 30/July/05
      • Dead reckoning Gary Martin 30/July/05
        • Dead reckoning Donald Cook 30/July/05
          • Dead reckoning Gary Martin 31/July/05
          • Dead reckoning R. Berg 31/July/05