(1)   Measuring instrument that consists of a float that trails from a ship by a knotted line in order to measure the ship's speed through the water
(2)   A written record of events on a voyage (of a ship or plane)
(3)   A written record of messages sent or received
"They kept a log of all transmission by the radio station"
"An email log"
(4)   The exponent required to produce a given number
(5)   A segment of the trunk of a tree when stripped of branches
(6)   Large log at the back of a hearth fire


(7)   Enter into a log, as on ships and planes
(8)   Cut lumber, as in woods and forests


  1. logarithm
    if x=b^y then log_{b}(x)=y

Etymology 1

Recorded since 1398, of unknown origin. The theory from is widely doubted on phonological grounds; an alternative is sound expression of the notion of something massive


  1. The trunk of a dead tree, cleared of branches.
    They walked across the stream on a fallen log.
  2. Any bulky piece as cut from the above, used as timber, fuel etc.
  3. A chip log, a device used in navigation to estimate the speed of a vessel through water.
  4. A logbook.
  5. A blockhead, very dumb person.
  6. A longboard.
    I know he hadn’t surfed on a log much in his childhood — Neal Miyake 1999 http://www.iav.com/~sponge/sesh/new2/sesh213.htm
  7. A rolled cake with filling; Swiss roll.


  1. To cut trees into logs
  2. To cut down (trees).
  3. To travel at a specified speed, as ascertained by log chip
  4. To cut down trees in an area, harvesting and transporting the logs as wood


  1. A logbook, or journal of a vessel (or aircraft)'s progress
  2. A record of performance etc.


  1. To make, to add an entry (or more) in a log(book).
  2. To travel (a distance) as shown in a logbook

Related terms
logbook, weblog/blog, log out/log off, log in/log on