Glossary

A definition will show up in this window whenever you select a key term from an Overview page. You can also find a key term manually by scrolling through the glossary or choosing a letter from the alphabetized menu below.

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Scroll down to see the "Y" terms

yardang

A mushroom-like column with a resistant rock perched on an eroding column of softer rock; created by wind abrasion in deserts where a resistant rock overlies softer layers of rock.

yazoo stream

A small tributary that runs parallel to the main river in a floodplain because the tributary is blocked from entering the main river by levees.

Younger Dryas

An interval of cooler temperatures, that took place 4,500 years ago, during a general warming/glacier-retreat period.