#fibril__filament__strand  a very slender natural or synthetic fiber
  supertype:  fiber__fibre  a slender and greatly elongated solid substance
  subtype:  barb  one of the parallel filaments projecting from the main shaft of a feather
  subtype:  cobweb.fibril__gossamer  filaments from a cobweb
  subtype:  chromatid  one of two identical strands into which a chromosome splits during mitosis
  subtype:  myofibril__myofibrilla  one of many contractile filaments that make up a striated muscle fiber
  subtype:  rhizoid  any of various slender filaments that function as roots in mosses and ferns and fungi etc
     subtype:  leak_fungus__ring_rot_fungus__Rhizopus_stolonifer  fungus causing soft watery rot in fruits and vegetables and rings of dry rot around roots of sweet potatoes
  subtype:  hypha  any of the threadlike filaments forming the mycelium of a fungus
     subtype:  conidiophore  a specialized fungal hypha that produces conidia
     subtype:  rhizomorph  a dense mass of hyphae forming a rootlike structure characteristic of many fungi
  subtype:  paraphysis  a sterile simple or branched filament or hair borne among sporangia; may be pointed or clubbed

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