plu·ma I. \ˈplümə\noun (pluralplu·mae \-(ˌ)mē, -ˌmī\) Etymology: New Latin, from Latin, small soft feather — more at fleece : contour feather II. noun (-s) Etymology: American Spanish, from Spanish, feather, from Latin, small soft feather : any of several Caribbean sparid porgies (genus Calamus)