yellowback

noun

1

: gold certificate

2

: a cheap and usually sensational novel

especially : one sold in yellow board or paper covers in the late 19th and early 20th centuries

3

: a freshwater mussel (Lampsilis anodontoides) of the Mississippi valley and southeastern U.S. having a heavy shell covered with yellow periostracum and highly valued for mother-of-pearl

Word History

Etymology

yellow entry 1 + back

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