What is specially or decisively characteristic of a disease; indicating with certainty a disease; as, a pathognomonic symptom. The true pathognomonic sign of love jealousy. Arbuthnot called?

pathognomonic — Specially or decisively characteristic of a disease; indicating with certainty a disease; as, a pathognomonic symptom. The true pathognomonic sign of love jealousy. Arbuthnot. (Webster's 1913.)

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