early 15c., "a sign, that which indicates," from Latin indicationem (nominative indicatio) "an indicating; valuation," noun of action from past participle stem of indicare "point out, show," from in- "into, in, on, upon" (from PIE root *en "in") + dicare "proclaim" (from PIE root *deik- "to show," also "pronounce solemnly").
