Lewis & Short

rādix, īcis (gen. plur. radicium, Cassiod. H. E. 1, 1; Jul. Val. Itin. Alex. 32 (75)), f. [Gr. ῤίζα, a root; ῤάδιξ, a shoot or twig; cf. ramus], a root of a plant (cf. stirps).

  1. I. Lit.
      1. 1. In gen. (mostly in plur.): radices agere, to strike root, Varr. R. R. 1, 37 fin.; Ov. R. Am. 106; id. M. 4, 254; Col. 5, 6, 8; Plin. 16, 31, 56, § 127; cf. infra, II.: capere radices, to take root, Cato, R. R. 133, 3; Plin. 17, 17, 27, § 123: penitus immittere radices, Quint. 1, 3, 5: emittere radices e capite, ex se, Col. 3, 18, 6; 5, 10, 13: descendunt radices, Plin. 16, 31, 56, § 129: arbores ab radicibus subruere, Caes. B. G. 6, 27, 4: herbas radice revellit, Ov. M. 7, 226: radicibus eruta pinus, Verg. A. 5, 449: segetem ab radicibus imis eruere, id. G. 1, 319.
        Sing.: (arbos) quae, quantum vertice ad auras, tantum radice in Tartara tendit, Verg. G. 2, 292; Plin. 16, 31, 56, § 128; Hor. Ep. 2, 2, 150; Ov. H. 5, 147.
      2. 2. In partic., an edible root, Caes. B. C. 3, 48; esp. a radish: Syriaca, Col. 11, 3, 16; 59: also simply radix, Pall. 1, 35, 5; Hor. S. 2, 8, 8; Ov. M. 8, 666 al.: dulcis, licorice, Scrib. Comp. 170.
    1. B. Transf.
      1. 1. The root, i. e. the lower part of an object, the foot of a hill, mountain, etc.
        In plur.: in radicibus Caucasi natus, Cic. Tusc. 2, 22, 52: in radicibus Amani, id. Fam. 15, 4, 9: sub ipsis radicibus montis, Caes. B. G. 7, 36; 7, 51 fin.; 69; id. B. C. 1, 41; 3, 85, 1 et saep.
        In sing.: a Palatii radice, Cic. Div. 1, 45, 101; Plin. 37, 10, 66, § 180.
      2. 2. That upon which any thing is fixed or rests (e. g. the tongue, a feather, a rock); a root, foundation (poet.; used alike in sing. and plur.): linguae, Ov. M. 6, 557: plumae, id. ib. 2, 583: saxi, Lucr. 2, 102; Ov. M. 14, 713.
      3. 3. Radix virilis = membrum virile, Cael. Aur. Tard. 2, 1, 13.
  2. II. Trop., a root, ground, basis, foundation, origin, source (almost entirely in the plur.): vera gloria radices agit atque etiam propagatur, Cic. Off. 2, 12, 43: virtus altissimis defixa radicibus, id. Phil. 4, 5, 13: audeamus non solum ramos amputare miseriarum, sed omnes radicum fibras evellere, id. Tusc. 3, 6, 13: facilitatis et patientiae, id. Cael. 6, 14: Pompeius eo robore vir, iis radicibus, i. e. so deeply rooted, firmly established in the State, id. Att. 6, 6, 4: illic radices, illic fundamenta sunt, Quint. 10, 3, 3: a radicibus evertere domum, from its foundation, utterly, Phaedr. 3, 10, 49: ex iisdem, quibus nos, radicibus natum (C. Marium), i. e. a native of the same city, Cic. Sest. 22, 50; Varr. R. R. 2, 8, 1; cf. in sing.: Apollinis se radice ortum, Plin. 35, 10, 36, § 72: ego sum radix David, Vulg. Apoc. 22, 16 et saep.
    Of words, origin, derivation, Varr. L. L. 6, 5, 61; 7, 3, 88 al.