Source : Webster's Revised Unabridged Dictionary (1913)

Oblique \Ob*lique"\, a. [F., fr. L. obliquus; ob (see {Ob-}) +
   liquis oblique; cf. licinus bent upward, Gr ? slanting.]
   [Written also {oblike}.]
   1. Not erect or perpendicular; neither parallel to, nor at
      right angles from, the base; slanting; inclined.

            It has a direction oblique to that of the former
            motion.                               --Cheyne.

   2. Not straightforward; indirect; obscure; hence,
      disingenuous; underhand; perverse; sinister.

            The love we bear our friends . . . Hath in it
            certain oblique ends.                 --Drayton.

            This mode of oblique research, when a more direct
            one is denied, we find to be the only one in our
            power.                                --De Quincey.

            Then would be closed the restless, oblique eye. That
            looks for evil, like a treacherous spy. --Wordworth.

   3. Not direct in descent; not following the line of father
      and son; collateral.

            His natural affection in a direct line was strong,
            in an oblique but weak.               --Baker.

   {Oblique angle}, {Oblique ascension}, etc. See under
      {Angle},{Ascension}, etc.

   {Oblique arch} (Arch.), an arch whose jambs are not at right
      angles with the face, and whose intrados is in consequence
      askew.

   {Oblique bridge}, a skew bridge. See under {Bridge}, n.

   {Oblique case} (Gram.), any case except the nominative. See
      {Case}, n.

   {Oblique circle} (Projection), a circle whose plane is
      oblique to the axis of the primitive plane.

   {Oblique fire} (Mil.), a fire the direction of which is not
      perpendicular to the line fired at.

   {Oblique flank} (Fort.), that part of the curtain whence the
      fire of the opposite bastion may be discovered. --Wilhelm.

   {Oblique leaf}. (Bot.)
      (a) A leaf twisted or inclined from the normal position.
      (b) A leaf having one half different from the other.

   {Oblique line} (Geom.), a line that, meeting or tending to
      meet another, makes oblique angles with it.

   {Oblique motion} (Mus.), a kind of motion or progression in
      which one part ascends or descends, while the other
      prolongs or repeats the same tone, as in the accompanying
      example.

Angle \An"gle\ ([a^][ng]"g'l), n. [F. angle, L. angulus angle,
   corner; akin to uncus hook, Gr. 'agky`los bent, crooked,
   angular, 'a`gkos a bend or hollow, AS. angel hook, fish-hook,
   G. angel, and F. anchor.]
   1. The inclosed space near the point where two lines meet; a
      corner; a nook.

            Into the utmost angle of the world.   --Spenser.

            To search the tenderest angles of the heart.
                                                  --Milton.

   2. (Geom.)
      (a) The figure made by. two lines which meet.
      (b) The difference of direction of two lines. In the lines
          meet, the point of meeting is the vertex of the angle.

   3. A projecting or sharp corner; an angular fragment.

            Though but an angle reached him of the stone.
                                                  --Dryden.

   4. (Astrol.) A name given to four of the twelve astrological
      ``houses.'' [Obs.] --Chaucer.

   5. [AS. angel.] A fishhook; tackle for catching fish,
      consisting of a line, hook, and bait, with or without a
      rod.

            Give me mine angle: we 'll to the river there.
                                                  --Shak.

            A fisher next his trembling angle bears. --Pope.

   {Acute angle}, one less than a right angle, or less than
      90[deg].

   {Adjacent} or {Contiguous angles}, such as have one leg
      common to both angles.

   {Alternate angles}. See {Alternate}.

   {Angle bar}.
      (a) (Carp.) An upright bar at the angle where two faces of
          a polygonal or bay window meet. --Knight.
      (b) (Mach.) Same as {Angle iron}.

   {Angle bead} (Arch.), a bead worked on or fixed to the angle
      of any architectural work, esp. for protecting an angle of
      a wall.

   {Angle brace}, {Angle tie} (Carp.), a brace across an
      interior angle of a wooden frame, forming the hypothenuse
      and securing the two side pieces together. --Knight.

   {Angle iron} (Mach.), a rolled bar or plate of iron having
      one or more angles, used for forming the corners, or
      connecting or sustaining the sides of an iron structure to
      which it is riveted.

   {Angle leaf} (Arch.), a detail in the form of a leaf, more or
      less conventionalized, used to decorate and sometimes to
      strengthen an angle.

   {Angle meter}, an instrument for measuring angles, esp. for
      ascertaining the dip of strata.

   {Angle shaft} (Arch.), an enriched angle bead, often having a
      capital or base, or both.

   {Curvilineal angle}, one formed by two curved lines.

   {External angles}, angles formed by the sides of any
      right-lined figure, when the sides are produced or
      lengthened.

   {Facial angle}. See under {Facial}.

   {Internal angles}, those which are within any right-lined
      figure.

   {Mixtilineal angle}, one formed by a right line with a curved
      line.

   {Oblique angle}, one acute or obtuse, in opposition to a
      right angle.

   {Obtuse angle}, one greater than a right angle, or more than
      90[deg].

   {Optic angle}. See under {Optic}.

   {Rectilineal} or {Right-lined angle}, one formed by two right
      lines.

   {Right angle}, one formed by a right line falling on another
      perpendicularly, or an angle of 90[deg] (measured by a
      quarter circle).

   {Solid angle}, the figure formed by the meeting of three or
      more plane angles at one point.

   {Spherical angle}, one made by the meeting of two arcs of
      great circles, which mutually cut one another on the
      surface of a globe or sphere.

   {Visual angle}, the angle formed by two rays of light, or two
      straight lines drawn from the extreme points of an object
      to the center of the eye.

   {For Angles of commutation}, {draught}, {incidence},
   {reflection}, {refraction}, {position}, {repose}, {fraction},
      see {Commutation}, {Draught}, {Incidence}, {Reflection},
      {Refraction}, etc.

Source : WordNet®

oblique angle
     n : an angle that is not a right angle or a multiple of a right
         angle [ant: {right angle}]