sliding

from The Century Dictionary.

• Slippery; uncertain; unstable; changing.
• Movable; graduated; varying; changing according to circumstances: as, a sliding scale (which see, under slide, v.).
• That slides; fitted for being slid.
• Sloping.
• noun The motion of a body along a plane when the same face or surface of the moving body keeps in contact with the surface of the plane: thus distinguished from rolling, in which the several parts of the moving body come successively in contact with the plane on which it roils.
• noun The sport of gliding on snow or ice, on the feet, on a sled or a toboggan, or (in former use) on skates, etc.
• noun Falling; lapse; merging.
• noun Transgression; lapse; backsliding.

from the GNU version of the Collaborative International Dictionary of English.

• adjective That slides or slips; gliding; moving smoothly.
• adjective obsolete Slippery; elusory.
• adjective (Mech.) the resistance one body meets with in sliding along the surface of another, as distinguished from rolling friction.
• adjective (Naut.) a topmast arranged with metallic fittings so as to be hoisted and lowered by means of halyards.
• adjective (Naut) a movable keel, similar to a centeboard.
• adjective (Mech.) See the Note under Pair, n., 7.
• adjective Same as Slide rule, under Slide, n.
• adjective A slide rule.
• adjective (Naut.) the timber guides used in launching a vessel.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• verb Present participle of slide.
• noun The motion of something that slides.
• adjective Of something that can slide

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• adjective being a smooth continuous motion