rachis


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Related to rachis: petiolule

ra·chis

 (rā′kĭs)
n. pl. ra·chis·es or rach·i·des (răk′ĭ-dēz′, rā′kĭ-)
1.
a. The main stem of an elongated inflorescence, as in a grass.
b. The main axis of a pinnately compound leaf or of a fern frond.
2. The main shaft of a bird's feather, especially the part to which the barbs are attached.
3. The spinal column.

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

ra′chi·al adj.

rachis

(ˈreɪkɪs) or

rhachis

n, pl rachises, rhachises, rachides or rhachides (ˈrækɪˌdiːz; ˈreɪ-)
1. (Botany) botany the main axis or stem of an inflorescence or compound leaf
2. (Zoology) ornithol the shaft of a feather, esp the part that carries the barbs
3. (Anatomy) another name for spinal column
[C17: via New Latin from Greek rhakhis ridge]
rachial, rhachial rachidial, rhachidial adj

ra•chis

(ˈreɪ kɪs)

n., pl. ra•chis•es, rach•i•des (ˈræk ɪˌdiz, ˈreɪ kɪ-)
1. any of various axial structures of a plant, as the stem of a leaflet.
2. the part of the shaft of a feather bearing the web.
[1775–85; < New Latin < Greek rháchis spine]
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.rachis - axis of a compound leaf or compound inflorescencerachis - 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 cordrachis - the series of vertebrae forming the axis of the skeleton and protecting the spinal cord; "the fall broke his 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
Translations

ra·chis

n. raquis, la columna vertebral.
References in periodicals archive ?
Pestalotiopsis also has been associated with rachis infections that result in berry shrivel in vinifera vineyards.
5 mm long, located on the rachis, between the proximal pairs to leaflets; rachis 35-125 mm long; interfoliolar segments 4-8 mm long; leaflets discolorous, 18-20 pairs, chartaceous, adaxial surface glabrous, abaxial surface pilose, 10-19.
Contract award notice: Sterile and implantable medical devices and consumables for orthopedic surgery (excluding rachis, hand and maxillo) - 2017.
5 cm long, oblong in outline; petioles 10-12 mm long, winged, somewhat aromatic when crushed; rachis more narrowly winged than petiole, involute when drying, and appearing quadrangular; leaflets 7-11, 5-6 x 6-9 mm, subsessile, semi-succulent, and broadly obovate to broadly elliptic, yellowish-green, opaque, midvein on abaxial surface prominent; indument spiculate on stems, reproductive structures glabrous, foliage with resinous papilla.
In the second stage, traditional postural descriptor parameters were characterized: a) Plantar footprint, b) Lumbo-pelvic equilibrium, c) Torso cervical segment, d) Torso lumbar segment, e) Rachis equilibrium, and f) Head equilibrium.
For each pair of corresponding bilateral leaflets, I measured four traits at the widest point of the leaflet: upper left (UL) and lower left (LL) for the leaflet residing on the left side of the rachis and upper right (UR) and lower right (LR) for the leaflet residing on the right side of the rachis.
Survived spikelets per panicle (SSPP), differentiated secondary rachis branches (SB) were determined.
Besides, rachis browning is also an important storage problem of grapes, which greatly affects consumer preference and fruit price [2].
This species is distinguished by its main axis of the synflorescence with 37-71 branches; first branch on the main axis of synflorescence with 34-49 branches; second branch on the main axis of synflorescence with 8-10 internodes; articulate rachis internodes 1.
Le neuronavigateur acquis par le CHU de Bejaia represente a ce jour le seul equipement sur le territoire national disposant du module rachis.
Tout le monde est expose au risque de tendinite : l'epaule est la localisation la plus frequente ainsi que d'autres articulations, le coude, le genou, le poignet, la cheville ou le rachis.