A new model explaining this mysterious process suggests the core was created as dribs and drabs of iron percolated inward from Earth's lower mantle, according to a study published Oct. 6 in the journal Nature Geoscience. The mantle is the viscous, rocky layer between the crust and Earth's iron core.
Definition of flash card. : a card bearing words, numbers, or pictures that is briefly displayed (as by a teacher to a class) usually as a learning aid.
a card game played by two or more persons, in which the players bet on the value of their hands, the winner taking the pool. Origin. 1825-35, Americanism; perhaps orig. braggart, bluffer; compare Middle Low German poken to brag, play, Middle Dutch poken to bluff, brag. Examples from the Web for poker.