hardpan

[ hahrd-pan ]

noun

1. any layer of firm detrital matter, as of clay, underlying soft soil. Compare caliche, duricrust.
2. hard, hard, unbroken ground.
3. the fundamental or basic aspect of anything; solid foundation; underlying reality:

   the hardpan of mathematical theory.

hardpan

/ ˈhɑːdˌpæn /

noun

1. a hard impervious layer of clay below the soil, resistant to drainage and root growth

hardpan

/ härd′păn′ /

1. A hard, usually clay-rich layer of soil lying at or just below the ground surface, in which soil particles are cemented together by silica, iron oxide, calcium carbonate, or organic matter that has precipitated from water percolating through the soil. Hardpans do not soften when exposed to water.
2. Also called caliche

Word History and Origins

Origin of hardpan¹

An Americanism dating back to 1810–20; hard + pan ¹

Example Sentences

Mike McCormack lives in Galway, Ireland, on a seacoast facing the Atlantic with rocky, unforgiving cliffs that give way to thin, hardpan soil.

From Los Angeles Times

He envisions a world where neighbors grow food to share with each other and those hardpan vacant lots and parkway strips between sidewalk and street are lush with birdsong, flowers and food-producing plants.

From Los Angeles Times

The hardpan streets had cuttingly sharp edges, but they also glinted with mica, which as a kid struck me like treasure — if you could dig it out, wouldn’t it be silver dust?

From Washington Post

Previously, gardeners used rototillers, which would produce a fluffy soil on top but, after 50 years of tilling, created a hardpan clay beneath.

From Washington Post

On the 13th, he couldn’t get a 5 1/2-foot eagle putt to fall after hitting a 208-yard second shot from the desert hardpan.

From Seattle Times