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Essential Black Cinema

essential ɪˌsɛnʃ(ə)l
adjective
1 absolutely necessary; extremely important : [with infinitive ] it is essential to keep up-to-date records | fiber is an essential ingredient. See notes at inherent, necessary .
[ attrib. ] fundamental or central to the nature of something or someone : the essential weakness of the plaintiff's case.

ORIGIN Middle English (in the sense [in the highest degree] ): from late Latin essentialis, from Latin essentia.