type of mineral that can be separated easily into extremely thin, tough laminae, 1706, from a Modern Latin specialized use of Latin mica "crumb, bit, morsel, grain." This is sometimes said to be from the same source as Attic Greek mikros "small" (see micro-). The word was applied to the mineral probably on the supposition that it was related to Latin micare "to flash, glitter" (see micacious). However a recent theory of the origin of the Latin noun does derive it from the same root as micare, on the notion of "a glittering crystalline particle" (originally a grain of salt), which de Vaan finds "formally more attractive" than the connection to the Greek word. Older native names for it were glimmer and cat-silver. Related: Micaceous "containing mica" (1748).
1580s, talke, from French talc (16c.), probably from Spanish talco and Medieval Latin talcus, also talcum "talc" (ealy 14c.), both from Arabic talq, from Persian talk "talc." "It was applied by the Arab and medieval writers to various transparent, translucent and shining minerals such as talc proper, mica, selenite, etc." [Flood]. Related: Talcoid; talcose; talcous.
as a type of a childishly impractical man living in optimistic fantasy, by 1852, from the character of Wilkins Micawber in Dickens' "David Copperfield" (1850).
"I am at present, my dear Copperfield, engaged in the sale of corn upon commission. It is not an avocation of a remunerative description — in other words it does not pay — and some temporary embarrassments of a pecuniary nature have been the consequence. I am however delighted to add that I have now an immediate prospect of something turning up ...."