a low wall dividing the circus lengthwise

spīna, ae, f. [root spī, whence also spicna, spīca, spinus], a thorn.

Lit.:

cum lubrica serpens Exuit in spinis vestem,

Lucr. 4, 61; cf. Prop. 4 (5), 5, 1; Verg. E. 5, 39; Col. 3, 11, 5; Plin. 21, 15, 54, § 91 al.:

consertum tegumen spinis,

Verg. A. 3, 594; cf. Ov. M. 14, 166; id. P. 2, 2, 36; Tac. G. 17. —Of particular kinds of thorny plants or shrubs:

solstitialis,

Col. 2, 18, 1:

alba,

whitethorn, hawthorn, id. 7, 7, 2; 7, 9, 6; 3, 11, 5; Plin. 21, 11, 39, § 68; 24, 12, 66, § 108: Aegyptia, the Egyptian blackthorn or sloe, id. 13, 11, 20, § 66; 24, 12, 65, § 107:

Arabica,

Arabian acacia, id. 24, 12, 65, § 107.—

Transf., of things of a like shape.

A prickle or spine of certain animals (as the hedgehog, sea-urchin, etc.): animantium aliae coriis tectae sunt, aliae villis vestitae, aliae spinis hirsutae, Cic. N. D. 2, 47, 121:

hystrices spinā contectae (with aculei),

Plin. 8, 35, 53, § 125; 9, 59, 85, § 182:

spinā nocuus,

Ov. Hal. 130.—

A fish-bone:

humus spinis cooperta piscium,

Quint. 8, 3, 66; Ov. M. 8, 244.—

The backbone, spine:

caput spina excipit: ea constat ex vertebris quattuor et viginti, etc.,

Cels. 8, 1; 8, 9, 2; 8, 14; Plin. 11, 37, 68, § 179; Varr. R. R. 2, 7, 5; Col. 6, 29, 2; Verg. G. 3, 87; Ov. M. 8, 806:

dorsi spina, Aug. Civ. Dei, 19, 4, n. 2: spina quae est in dorso,

Gell. 3, 10, 7.— Hence, poet., the back, Ov. M. 6, 380; 3, 66; 3, 672.—

Spina, a low wall dividing the circus lengthwise, around which was the race-course; the barrier, Cassiod. Var. 3, 51; Schol. Juv. 6, 588.—

A toothpick:

argentea,

Petr. 32 fin. —

Trop., in plur.

Thorns, i. e. difficulties, subtleties, perplexities in speaking and debating (class.):

disserendi spinae,

Cic. Fin. 4, 28, 79; cf.:

partiendi et definiendi,

subtleties, intricacies, id. Tusc. 4, 5, 9; cf.:

hominum more non spinas vellentium, ut Stoici,

id. Fin. 4, 3, 6.—

Cares:

certemus, spinas animone ego fortius an tu Evellas agro,

Hor. Ep. 1, 14, 4.—

Errors:

quid te exemta juvat spinis de pluribus una,

Hor. Ep. 2, 2, 212.