mercurial
adj
1
(a) (of people or their moods, etc) often changing (指人或情緒等)多變的, 無常的
a mercurial temperament 喜怒無常的性情.
(b) lively; quick-witted 活潑的; 機智的
She has a mercurial turn of conversation. 她談話善轉話鋒.
2 (fml or medical 文或醫) of, like, containing or caused by mercury 汞的; (像)水銀的; 含水銀的; 水銀引起的
a mercurial ointment, compound, etc 含汞藥膏、 汞化合物
mercurial poisoning 汞中毒.