1. (a.) Pertaining to the root; a person firmly devoted to a basic root belief\.

2. (a.) Hence: Of or pertaining to the root or origin; reaching to the center, to the foundation, to the ultimate sources, to the principles, or the like; original; fundamental; thorough-going; unsparing; extreme; as, radical evils; radical reform; a radical party.

3. (a.) Belonging to, or proceeding from, the root of a plant; as, radical tubers or hairs.

4. (a.) Proceeding from a rootlike stem, or one which does not rise above the ground; as, the radical leaves of the dandelion and the sidesaddle flower.

5. (a.) Relating, or belonging, to the root, or ultimate source of derivation; as, a radical verbal form.

6. (a.) of or pertaining to a radix or root; as, a radical quantity; a radical sign. See below.

7. (n.) A primitive word; a radix, root, or simple, underived, uncompounded word; an etymon.

8. (n.) A primitive letter; a letter that belongs to the radix.

9. (n.) One who advocates radical changes in government or social institutions, especially such changes as are intended to level class inequalities; -- opposed to conservative.

10. (n.) A characteristic, essential, and fundamental constituent of any compound; hence, sometimes, an atom.

11. (n.) Specifically, a group of two or more atoms, not completely saturated, which are so linked that their union implies certain properties, and are conveniently regarded as playing the part of a single atom; a residue; -- called also a compound radical. Cf. Residue.

12. (n.) A radical quantity. See under Radical, a.

13. (n.) A radical vessel. See under Radical, a.

Bolshevik Bolshevist Fabian Gospel side IC analysis Jacobin Kekule formula Wobbly ab ovo aboriginal absolute accidence acid acidity advanced affix affixation agent agitator algorismic algorithmic aliquot alkali alkalinity all-embracing all-encompassing all-inclusive all-out all-pervading alloisomer allomorph anarchist anarchistic anarcho-syndicalist anion antacid arrowhead at the height at the limit atom atomic cluster basal base basement basic basilar basis bearing wall bed bedding bedrock beginning benzene ring biochemical born bottom bound morpheme branched chain broad broad-based broad-minded cantorial side cardinal cataclysmic catastrophic cation central chain character chemical chemical element chromoisomer clean clear closed chain commencement communist complete compound compound radical comprehensive conception congenital conjugation constituent constitutional constitutive consummate copolymer corrective counterclockwise crucial cuneiform cutting cycle decimal declension deep deep-dyed deep-seated demotic character derivation determinative difference of form differential digital dimer downright drastic dyad dyed-in-the-wool egregious element elemental elementary embryonic emendatory enclitic entire essential even exhaustive exponential extreme extreme left-winger extremist extremistic fanatic fanatical far out figural figurate figurative finite floor flooring fond footing formative foundation foundational fractional free form fundament fundamental furthest generative genesis genetic germinal gradualistic grammalogue grass roots greatest ground grounds groundwork gut hardpan head heavy chemicals heptad heterocycle hexad hieratic symbol hieroglyph hieroglyphic hieroglyphics high polymer hiragana homocycle homopolymer hydracid ideogram ideograph imaginary immediate constituent analysis immoderate impair impossible in embryo in ovo inception infinite infix infixation inflection inherent inorganic chemical insurgent insurrectionary insurrectionist integral intensive intrinsic ion irrational isomer kana katakana larboard lattice left left hand left wing left-hand left-hand side left-wing left-wing extremist left-winger left-wingish leftist levorotatory liberal logarithmic logogram logograph logometric lunatic fringe macromolecule material meliorist melioristic metamer mild radical mildly radical militant molecule monad monomer morph morpheme morphemic analysis morphemics morphology morphophonemics most natural near near side negative neutralizer nigh nihilist nihilistic nonacid numeral numerary numerative numeric octad odd of the essence ogham