prog·nos·tic 
(prŏg-nŏstĭk)
(prŏg-nŏstĭk)adj.
1. Of, relating to, or useful in prognosis.
2. Of or relating to prediction; predictive.
n.
1. A sign or symptom indicating the future course of a disease.
2. A sign of a future happening; a portent.
[Middle English pronostik, prognosticating, omen, from Medieval Latin prognōsticus, prognosticating, from Greek prognōstikos, from prognōsis, foreknowledge; see PROGNOSIS. N., from Latin prognōsticum, omen, from Greek prognōstikon, from neuter of prognōstikos.]