filament

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun A fine or very thin thread or fiber.
• noun A slender or threadlike structure or part, especially.
• noun A fine wire that is heated electrically to produce light in an incandescent lamp.
• noun The stalk that bears the anther in the stamen of a flower.
• noun A chainlike series of cells, as in many algae.
• noun A long thin cellular structure characteristic of many fungi, usually having multiple nuclei and often divided by septa.
• noun Any of various long thin celestial objects or phenomena, such as a solar filament.

from The Century Dictionary.

• noun In geometrical topics, a movable object which at any one instant, or indivisible determination of time, is at every part of a line. During a lapse of time a filament is restricted to being in some surface, which it is said to generate.
• noun A long threadlike bacterial growth.
• noun A fine untwisted thread; a separate fiber or fibril of any vegetable or animal tissue or product, natural or artificial, or of a fibrous mineral: as, a filament of silk, wool, cobweb, or asbestos; a cortical or muscular filament.
• noun Specifically In botany, the support of an anther, usually slender and stalk-like, but very variable in form.
• noun In ornithology, the part of a down-feather corresponding to the barb of an ordinary feather.
• noun A tenuous thread of any substance, as glass or mucus; hence, in medicine, a glairy substance sometimes contained in urine, capable of being drawn out into threads or strings.
• noun The nearly infusible conductor placed in the globe of an incandescent lamp or glow-lamp and raised to incandescence by the passage of the current. It is usually some form of carbon, although metals with high points of fusion have been used.

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

• noun (Bot.) A thread or threadlike object or appendage; a fiber

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

• noun A fine thread or wire.
• noun Such a wire, as can be heated until it glows, in an incandescent light bulb or a thermionic valve.
• noun physics, astronomy A massive, thread-like structure, such as those gaseous ones which extend outward from the surface of the sun, or such as those (much larger) ones which form the boundaries between large voids in the universe.
• noun botany The stalk of a stamen in a flower, supporting the anther.
• noun textiles A continuous object, limited in length only by its spool, and not cut to length.

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

• noun a thin wire (usually tungsten) that is heated white hot by the passage of an electric current
• noun a very slender natural or synthetic fiber
• noun a threadlike structure (as a chainlike series of cells)
• noun the stalk of a stamen