tar spot

noun

1
a
: a leaf-blotch disease of maple, willow, or oak caused by fungi of the genus Rhytisma that produces raised black stromatic cushions on the foliage
b
: one of the spots produced
2
: a disease of many grasses caused by a fungus (Phyllacora graminis) and resembling the tar spot of trees

Word History

Etymology

tar entry 1

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Dictionary Entries Near tar spot

Cite this Entry

“Tar spot.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/tar%20spot. Accessed 18 Apr. 2024.

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