rachis or rha·chis [rey-kis] Word Origin noun, plural ra·chis·es, rach·i·des [rak-i-deez, rey-ki-] /ˈræk ɪˌdiz, ˈreɪ kɪ-/.

  1. Botany.
    1. the axis of an inflorescence when somewhat elongated, as in a raceme.
    2. (in a pinnately compound leaf or frond) the prolongation of the petiole along which the leaflets are disposed.
    3. any of various axial structures.
  2. Ornithology. the part of the shaft of a feather bearing the web.
  3. Anatomy. spinal column.

Origin of rachis 1775–85; New Latin Greek rháchis spine, ridge, backboneRelated formsra·chid·i·an [ruh-kid-ee-uh n] /rəˈkɪd i ən/, ra·chi·al [rey-kee-uh l] /ˈreɪ ki əl/, ra·chid·i·al, adjective British Dictionary definitions for rachial rachis rhachis noun plural rachises, rhachises, rachides or rhachides (ˈrækɪˌdiːz, ˈreɪ-)

  1. botany the main axis or stem of an inflorescence or compound leaf
  2. ornithol the shaft of a feather, esp the part that carries the barbs
  3. another name for spinal column

Derived Formsrachial or rhachial (ˈreɪkɪəl) or rachidial or rhachidial (rəˈkɪdɪəl), adjectiveWord Origin for rachis C17: via New Latin from Greek rhakhis ridge rachial in Medicine rachial [rā′kē-əl] adj.

  1. Rachidial.

rachis [rā′kĭs] n. pl. ra•chis•es

  1. spinal column

rachial in Science rachis [rā′kĭs] Plural rachises rachides (răk′ĭ-dēz′, rā′kĭ-)

  1. A main axis or shaft, such as the main stem of an inflorescence, the stalk of a pinnately compound leaf, the shaft of a feather, or the spinal column.

Leave a Reply

Your email address will not be published. Required fields are marked *

46 queries 0.968