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isochrone

[ahy-suh-krohn]
noun
  1. a line, as on a map, connecting all points having some property simultaneously, as in having the same delay in receiving a radio signal from a given source or requiring the same time to be reached by available transportation from a given center.

Origin of isochrone

1690–1700; back formation from isochronous or isochronal
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for isochrone

isochrone

noun
  1. a line on a map or diagram connecting places from which it takes the same time to travel to a certain point
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012