The Collaborative International Dictionary of English v.0.48:

Secondary \Sec"ond*a*ry\, a. [Cf. F. secondaire, L. secundaire.
   See Second, a.]
   1. Succeeding next in order to the first; of second place,
      origin, rank, etc.; not primary; subordinate; not of the
      first order or rate.
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            Wheresoever there is moral right on the one hand, no
            secondary right can discharge it.     --L'Estrange.
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            Two are the radical differences; the secondary
            differences are as four.              --Bacon.
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   2. Acting by deputation or delegated authority; as, the work
      of secondary hands.
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   3. (Chem.) Possessing some quality, or having been subject to
      some operation (as substitution), in the second degree;
      as, a secondary salt, a secondary amine, etc. Cf.
      primary.
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   Note: A primary amine has the general formula R.NH2; a
         secondary amine has the general formula R.NH.R',
         where R and R' are alkyl or aryl groups. A primary
         alcohol has the general formula R.CH2.OH; a secondary
         alcohol has the general formula R.CHOH.R'. Tertiary
         amines and alcohols have the general formulas
         R.CR'N.R' and R.CR'OH.R', respectively.
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   4. (Min.) Subsequent in origin; -- said of minerals produced
      by alteration or deposition subsequent to the formation of
      the original rock mass; also of characters of minerals (as
      secondary cleavage, etc.) developed by pressure or other
      causes.
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   5. (Zool.) Pertaining to the second joint of the wing of a
      bird.
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   6. (Med.)
      (a) Dependent or consequent upon another disease; as,
          Bright's disease is often secondary to scarlet fever.
      (b) Occurring in the second stage of a disease; as, the
          secondary symptoms of syphilis.
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   Secondary accent. See the Note under Accent, n., 1.

   Secondary age. (Geol.) The Mesozoic age, or age before the
      Tertiary. See Mesozoic, and Note under Age, n., 8.

   Secondary alcohol (Chem.), any one of a series of alcohols
      which contain the radical CH.OH united with two
      hydrocarbon radicals. On oxidation the secondary alcohols
      form ketones.

   Secondary amputation (Surg.), an amputation for injury,
      performed after the constitutional effects of the injury
      have subsided.

   Secondary axis (Opt.), any line which passes through the
      optical center of a lens but not through the centers of
      curvature, or, in the case of a mirror, which passes
      through the center of curvature but not through the center
      of the mirror.

   Secondary battery. (Elec.) See under Battery, n., 4.

   Secondary circle (Geom. & Astron.), a great circle that
      passes through the poles of another great circle and is
      therefore perpendicular to its plane.

   Secondary circuit, Secondary coil (Elec.), a circuit or
      coil in which a current is produced by the induction of a
      current in a neighboring circuit or coil called the
      primary circuit or coil.

   Secondary color, a color formed by mixing any two primary
      colors in equal proportions.

   Secondary coverts (Zool.), the longer coverts which overlie
      the basal part of the secondary quills of a bird. See
      Illust. under Bird.

   Secondary crystal (Min.), a crystal derived from one of the
      primary forms.

   Secondary current (Elec.), a momentary current induced in a
      closed circuit by a current of electricity passing through
      the same or a contiguous circuit at the beginning and also
      at the end of the passage of the primary current.

   Secondary evidence, that which is admitted upon failure to
      obtain the primary or best evidence.

   Secondary fever (Med.), a fever coming on in a disease
      after the subsidence of the fever with which the disease
      began, as the fever which attends the outbreak of the
      eruption in smallpox.

   Secondary hemorrhage (Med.), hemorrhage occuring from a
      wounded blood vessel at some considerable time after the
      original bleeding has ceased.

   Secondary planet. (Astron.) See the Note under Planet.

   Secondary qualities, those qualities of bodies which are
      not inseparable from them as such, but are dependent for
      their development and intensity on the organism of the
      percipient, such as color, taste, odor, etc.

   Secondary quills or Secondary remiges (Zool.), the quill
      feathers arising from the forearm of a bird and forming a
      row continuous with the primaries; -- called also
      secondaries. See Illust. of Bird.

   Secondary rocks or Secondary strata (Geol.), those lying
      between the Primary, or Paleozoic, and Tertiary (see
      Primary rocks, under Primary); -- later restricted to
      strata of the Mesozoic age, and at present but little
      used.

   Secondary syphilis (Med.), the second stage of syphilis,
      including the period from the first development of
      constitutional symptoms to the time when the bones and the
      internal organs become involved.

   Secondary tint, any subdued tint, as gray.

   Secondary union (Surg.), the union of wounds after
      suppuration; union by the second intention.
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   Syn: Second; second-rate; subordinate; inferior.
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