rachis

ra·chis  (rks)

n. pl. ra·chis·es or rach·i·des (rk-dz, rk-) Biology

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

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[New Latin, from Greek rhakhis, spine, ridge.]

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rachi·al adj.

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rachis, rhachis [ˈreɪkɪs]

n pl rachises, rhachises, rachides rhachides [ˈrækɪˌdiːz ˈreɪ-]

1. (Life Sciences & Allied Applications / Botany) Botany the main axis or stem of an inflorescence or compound leaf

2. (Life Sciences & Allied Applications / Zoology) Ornithol the shaft of a feather, esp the part that carries the barbs

3. (Life Sciences & Allied Applications / Anatomy) another name for vertebral column

[via New Latin from Greek rhakhis ridge]

rachial , rhachial [ˈreɪkɪəl], rachidial, rhachidial [rəˈkɪdɪəl] adj

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rachis  (rks)

Plural rachises or rachides (rk-dz, rk-)

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.

Thesaurus

Noun	1.	rachis - axis of a compound leaf or compound inflorescence axis - the main stem or central part about which plant organs or plant parts such as branches are arranged
	2.	rachis - the series of vertebrae forming the axis of the skeleton and protecting the spinal cord; "the fall broke his back" spinal column, spine, vertebral column, backbone, back notochord - a flexible rodlike structure that forms the supporting axis of the body in the lowest chordates and lowest vertebrates and in embryos of higher vertebrates chine - backbone of an animal canalis vertebralis, spinal canal, vertebral canal - the canal in successive vertebrae through which the spinal cord passes coccyx, tail bone - the end of the vertebral column in humans and tailless apes vertebra - one of the bony segments of the spinal column intervertebral disc, intervertebral disk - a fibrocartilaginous disc serving as a cushion between all of the vertebrae of the spinal column (except between the first two) skeletal structure - any structure created by the skeleton of an organism axial skeleton - the part of the skeleton that includes the skull and spinal column and sternum and ribs