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Related to rachis: petiolule


n. pl. ra·chis·es or rach·i·des (răk′ĭ-dēz′, rā′kĭ-)
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.


(ˈreɪkɪs) or


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


(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


n. raquis, la columna vertebral.
References in periodicals archive ?
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.
While the grain only allows a determination to the level of a broad category of free-threshing wheats (Triticum aestivum/durum), the morphology of the rachis segments is characteristic of hexaploid bread wheat (T.
This latter character is absent in Florida material, in which all the lobes diverge from the central rachis at the same angle.
In addition to be among the leading causes of many diseases such as sleep apnea and sleep disorders, these diseases have also a direct impact on the stomatognathic apparatus, composed of several muscles connected to cranio-mandibular structures, to the rachis, to the shoulder girdle and upper limbs.
The observer used the angle tool to demarcate the boundaries of the black coloration in the middle of the feather vane, on either side of the rachis to compute the angle (to [+ or -]0.
Metabolic profiling of the flower bud and rachis of Tussilago farfara with antitussive and expectorant effects on mice.
Petiole and rachis with very few to no prickles, leaflet surface rather flat, margins with small scattered serrations, especially in proximal end, leaflet tip acute 4 4.
The RACHIS Recoil System for full- and compact-frame Glock GEN 4 pistols is now available.
Mihamadawi statements stirred reactions against him that denounced rachis inclinations of the call.
12:00 Mufti of Lebanon Sheikh Mohammad Rachis Qabbani to receive at Dar Fatwa Swiss Ambassador
Rachis cunctatoris: Bruggen 1975: 217, figs 7-9 (Lower Shire Valley, southern Malawi; 18.