The Collaborative International Dictionary of English v.0.48:
Parallel \Par"al*lel\, a. [F. parall[`e]le, L. parallelus, fr.
Gr. ?; para` beside + ? of one another, fr. ? other, akin to
L. alius. See Alien.]
1. (Geom.) Extended in the same direction, and in all parts
equally distant; as, parallel lines; parallel planes.
Revolutions . . . parallel to the equinoctial.
Note: Curved lines or curved planes are said to be parallel
when they are in all parts equally distant.
2. Having the same direction or tendency; running side by
side; being in accordance (with); tending to the same
result; -- used with to and with.
When honor runs parallel with the laws of God and
our country, it can not be too much cherished.
3. Continuing a resemblance through many particulars;
applicable in all essential parts; like; similar; as, a
parallel case; a parallel passage. --Addison.
(a) (Steam Eng.) A rod in a parallel motion which is
parallel with the working beam.
(b) One of a pair of bars raised about five feet above the
floor or ground, and parallel to each other, -- used
for gymnastic exercises.
Parallel circles of a sphere, those circles of the sphere
whose planes are parallel to each other.
Parallel columns, or Parallels (Printing), two or more
passages of reading matter printed side by side, for the
purpose of emphasizing the similarity or discrepancy
Parallel forces (Mech.), forces which act in directions
parallel to each other.
(a) (Mach.) A jointed system of links, rods, or bars, by
which the motion of a reciprocating piece, as a piston
rod, may be guided, either approximately or exactly in
a straight line. --Rankine.
(b) (Mus.) The ascending or descending of two or more
parts at fixed intervals, as thirds or sixths.
Parallel rod (Locomotive Eng.), a metal rod that connects
the crank pins of two or more driving wheels; -- called
also couping rod, in distinction from the connecting
rod. See Illust. of Locomotive, in App. -- Parallel
ruler, an instrument for drawing parallel lines, so
constructed as to have the successive positions of the
ruling edge parallel to each other; also, one consisting
of two movable parts, the opposite edges of which are
Parallel sailing (Naut.), sailing on a parallel of
Parallel sphere (Astron. & Geog.), that position of the
sphere in which the circles of daily motion are parallel
to the horizon, as to an observer at either pole.
Parallel vise, a vise having jaws so guided as to remain
parallel in all positions.