a. [f. ECHIN-US + -AL.] Of or belonging to a sea-urchin.
1830. Lyell, Princ. Geol., I. 129, note. A saurian vertebra together with patellæ and echinal spines.
a. [f. ECHIN-US + -AL.] Of or belonging to a sea-urchin.
1830. Lyell, Princ. Geol., I. 129, note. A saurian vertebra together with patellæ and echinal spines.