The Collaborative International Dictionary of English v.0.48:
Parallel \Par"al*lel\, n.
1. A line which, throughout its whole extent, is equidistant
from another line; a parallel line, a parallel plane, etc.
Who made the spider parallels design,
Sure as De Moivre, without rule or line ? --Pope.
2. Direction conformable to that of another line,
Lines that from their parallel decline. --Garth.
3. Conformity continued through many particulars or in all
essential points; resemblance; similarity.
Twixt earthly females and the moon
All parallels exactly run. --Swift.
4. A comparison made; elaborate tracing of similarity; as,
Johnson's parallel between Dryden and Pope.
5. Anything equal to, or resembling, another in all essential
particulars; a counterpart.
None but thyself can be thy parallel. --Pope.
6. (Geog.) One of the imaginary circles on the surface of the
earth, parallel to the equator, marking the latitude;
also, the corresponding line on a globe or map; as, the
counry was divided into North and South at the 38th
[1913 Webster +PJC]
7. (Mil.) One of a series of long trenches constructed before
a besieged fortress, by the besieging force, as a cover
for troops supporting the attacking batteries. They are
roughly parallel to the line of outer defenses of the
8. (Print.) A character consisting of two parallel vertical
lines (thus, ) used in the text to direct attention to a
similarly marked note in the margin or at the foot of a
9. (Elec.) That arrangement of an electrical system in which
all positive poles, electrodes, terminals, etc., are
joined to one conductor, and all negative poles, etc., to
another conductor; -- called also multiple. Opposed to
Note: Parts of a system so arranged are said to be
in parallel or
[Webster 1913 Suppl.]
Limiting parallels. See under Limit, v. t.
Parallel of altitude (Astron.), one of the small circles of
the sphere, parallel to the horizon; an almucantar.
Parallel of declination (Astron.), one of the small circles
of the sphere, parallel to the equator.
Parallel of latitude.
(a) (Geog.) See def. 6. above.
(b) (Astron.) One of the small circles of the sphere,
parallel to the ecliptic.