What is of, pertaining to, or designating, a substance (called ophelic acid) extracted from a plant (Ophelia) of the Gentian family as a bitter yellowish sirup, used in India as a febrifuge and tonic called?

ophelic — Of, pertaining to, or designating, a substance (called ophelic acid) extracted from a plant (Ophelia) of the Gentian family as a bitter yellowish sirup, used in India as a febrifuge and tonic. (Webster's 1913.)

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