Webster’s Revised Unabridged Dictionary · 1913
Dirigent
Dir′i·gent (·jent), a. [L. dirigens, p. pr. of dirigere. See Direct, a.] Directing. Baxter.
Dir′i·gent, n. (Geom.) 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.