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interfinger

American  
[in-ter-fing-ger] / ˌɪn tərˈfɪŋ gər /

verb (used without object)

Geology.
  1. (of sedimentary rocks) to change laterally from one type to another in a zone where the two types form interpenetrating wedges.


Etymology

Origin of interfinger

First recorded in 1970–75; inter- + finger