rachis

noun ra·chis \ˈrā-kəs, ˈra-\

plural ra·chis·es also ra·chi·des \ˈra-kə-ˌdēz, ˈrā-\

Definition of RACHIS

: an axial structure: as

a (1) : the elongated axis of an inflorescence (2) : an extension of the petiole of a compound leaf that bears the leaflets

b : the distal part of the shaft of a feather that bears the web

New Latin rachid-, rachis, from Greek rhachis; akin to Greek rhachos thorn, Lithuanian ražas dry twig, tine

First Known Use: 1785

Next Word in the Dictionary: rachiticPrevious Word in the Dictionary: rachionAll Words Near: rachis

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