a. Also si-. [f. prec. + -IC. So F. syénitique.] Of, pertaining to, composed of, allied to, or having the character of syenite.
1799. Kirwan, Geol. Ess., 343. The porphyritic and sienitic hills.
1835. R. Griffith, in Trans. Geol. Soc. (1840), Ser. II. V. 180. Two … veins of syenite, which pass into syenitic greenstone.
1868. Watts, Dict. Chem., V. 647. The occurrence or hornblende in granite renders it more or less syenitic.
