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isohel

American  
[ahy-suh-hel] / ˈaɪ səˌhɛl /

noun

Meteorology.
  1. a line on a weather map connecting points that receive equal amounts of sunshine.


isohel British  
/ ˈaɪsəʊˌhɛl /

noun

  1. a line on a map connecting places with an equal period of sunshine

"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

isohel Scientific  
/ īsō-hĕl′ /
  1. A line drawn on a weather map connecting points that receive equal amounts of sunlight.


Etymology

Origin of isohel

1900–05; iso- + -hel < Greek hḗlios sun