[uhn-der-kast, -kahst]
  1. Mining. a crossing of two passages, as airways, dug at the same level so that one descends to pass beneath the other without any opening into it.Compare overcast(def 9).
  2. Meteorology. an overcast layer of clouds viewed from above.

Origin of undercast

First recorded in 1880–85; under- + cast
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

Examples from the Web for undercast

Historical Examples of undercast