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sept'-foil, n. a plant, the roots of which are used in medicine, tanning, &c.: a figure of seven equal segments of a circle used in the R.C. Church as a symbol of her seven sacraments, the seven gifts of the Holy Spirit, &c. [Fr. sept--L. septem, seven, foil--L. folium, a leaf.]

n. [Latin] A plant of the genus Torment ilia, the roots of which are used in tanning, and in dyeing leather and worsted yarn, and also in medicine as an astringent;— an architectural ornament radiating from a centre in seven branches or leaves, or consisting of seven segments of a circle.