The Collaborative International Dictionary of English v.0.48:

Loxodromic \Lox`o*drom"ic\, a. [Gr. ? slanting, oblique + ? a
   running, course; cf. F. loxodromique.]
   Pertaining to sailing on rhumb lines; as, loxodromic tables.
   [1913 Webster]

   Loxodromic curve or Loxodromic line (Geom.), a line on
      the surface of a sphere, which always makes an equal angle
      with every meridian; the rhumb line. It is the line on
      which a ship sails when her course is always in the
      direction of one and the same point of the compass.
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Rhumb \Rhumb\, n. [F. rumb, Sp. rumbo, or Pg. rumbo, rumo,
   probably fr. Gr. ??? a magic wheel, a whirling motion, hence
   applied to a point of the compass. See Rhomb.] (Navigation)
   A line which crosses successive meridians at a constant
   angle; -- called also rhumb line, and loxodromic curve.
   See Loxodromic.
   [1913 Webster]

   To sail on a rhumb, to sail continuously on one course,
      following a rhumb line.
      [1913 Webster]