graphite Meaning, Definition & Usage

  1. noun used as a lubricant and as a moderator in nuclear reactors
    black lead; plumbago.

WordNet

Graph"ite noun
Etymology
Gr. to write: cf. F. graphite. See Graphic.
Definitions
  1. (Min.) Native carbon in hexagonal crystals, also foliated or granular massive, of black color and metallic luster, and so soft as to leave a trace on paper. It is used for pencils (improperly called lead pencils), for crucibles, and as a lubricator, etc. Often called plumbago or black lead.

Webster 1913