rachis /ˈreɪkɪs 
/ (also rhachis) ▸ noun (plural rachides /ˈreɪkɪdiːz/) 1 Botany a stem of a plant, especially a grass, bearing flower stalks at short intervals. ▪ the midrib of a compound leaf or frond.
2 Anatomy the vertebral column or the cord from which it develops. 3 Ornithology the shaft of a feather, especially the part bearing the barbs. – DERIVATIVES rachidial /rəˈkɪdɪəl/ adjective – ORIGIN late 17th century: via French and modern Latin from Greek rhakhis ‘spine’. The English plural -ides is by false analogy.
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