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isopectic

American  
[ahy-suh-pek-tik] / ˌaɪ səˈpɛk tɪk /

noun

  1. a line drawn on a map connecting all points where ice starts to form at approximately the same period at the onset of winter.


Etymology

Origin of isopectic

iso- + -pectic < Greek pēktikós freezing; pectic