sat·ur·nine 
(sătər-nīn′)
(sătər-nīn′)adj.
1. Having the temperament of one born under the supposed astrological influence of Saturn.
2.
a. Melancholy or sullen.
b. Having or marked by a tendency to be bitter or sardonic: a saturnine expression on his face.
3. Produced by absorption of lead.
satur·nine′ly adv.