noun
GeologyA narrow, sediment-filled rift valley which is thought to be the remnant of an incipient rift that failed to open further, typically one that initially formed a triple or quadruple junction with other rifts that developed fully.
Origin
1960s. From Russian avlakogen (N. S. Šatskij 1960) from ancient Greek αὖλακ-, αὖλαξ furrow (from the same Indo-European base as Old Church Slavonic vlěšti, Lithuanian vilkti to pull, to drag) + Russian -o- + -gen.
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