from The American Heritage® Dictionary of the English Language, 4th Edition
- n. A four-sided plane figure with opposite sides parallel.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. A convex quadrilateral in which each pair of opposite edges are parallel and of equal length.
from the GNU version of the Collaborative International Dictionary of English
- n. A right-lined quadrilateral figure, whose opposite sides are parallel, and consequently equal; -- sometimes restricted in popular usage to a rectangle, or quadrilateral figure which is longer than it is broad, and with right angles.
from The Century Dictionary and Cyclopedia
- n. In geometry, a quadrilateral whose opposite sides are parallel.
- n. A pantograph.
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- n. a quadrilateral whose opposite sides are both parallel and equal in length
Late Latin parallēlogrammum, from Greek parallēlogrammon, from neuter sing. of parallēlogrammos, bounded by parallel lines : parallēlos, parallel; see parallel + grammē, line; see gerbh- in Indo-European roots.(American Heritage® Dictionary of the English Language, Fourth Edition)