mast
rhymes with "fast"
The collective fruit of forest trees — acorns, beechnuts, hickory nuts, chestnuts — especially as food for wildlife. A "mast year" is a year of heavy production, when the forest floor is carpeted with nuts and the animals that depend on them — deer, bears, squirrels, turkeys, jays — feast. Mast years are irregular and synchronized across large areas, a reproductive strategy that overwhelms seed predators through sheer abundance.
Etymology
Old English mæst, meaning the fruit of forest trees, especially as food for swine. The word has been in English for over a thousand years, surviving because the phenomenon it names has never stopped mattering.
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