mer·cu·ri·al
mərˌkyo͝orēəl/
adjective
- 1.(of a person) subject to sudden or unpredictable changes of mood or mind."his mercurial temperament"
synonyms: volatile, capricious, temperamental, excitable, fickle, changeable,unpredictable, variable, protean, mutable, erratic, quicksilver,inconstant, inconsistent, unstable, unsteady, fluctuating, ever-changing, moody, flighty, wayward, whimsical, impulsive; More - 2.of or containing the element mercury.
noun
- 1.a drug or other compound containing mercury.