dirigent

Dir"i*gent, a. Etym: [L. dirigens, p. pr. of dirigere. See Direct, a.] Defn: Directing. Baxter. Dir"i*gent, n. (Geom.) Defn: The line of motion along which a describent line or surface is carried in the genesis of any plane or solid figure; a directrix. Hutton.

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