1. A fine or very thin thread or fiber: filaments of cloth; filaments of flax.
2. A slender or threadlike structure or part, especially:
a. A fine wire that is heated electrically to produce light in an incandescent lamp.
b. The stalk that bears the anther in the stamen of a flower.
c. A chainlike series of cells, as in many algae.
d. A long thin cellular structure characteristic of many fungi, usually having multiple nuclei and often divided by septa.
e. Any of various long thin celestial objects or phenomena, such as a solar filament.
[New Latin fīlāmentum, from Late Latin fīlāre, to spin, from Latin fīlum, thread; see gwhī- in the Appendix of Indo-European roots.]
fil′a·mentous (-mĕntəs), fil′a·menta·ry (-mĕntə-rē, -mĕntrē) adj.
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