levity
n.
"want of seriousness, frivolity," 1560s, from Latin levitatem (nominative levitas) "lightness, frivolity," from levis "light" in weight (see lever) + -ity.
〔李〕[lev;-ityn.] n.轻率； 变化无常 ←lev (L levare)=to raise or relieve举起； 减轻
〔蒋〕[lev举，升，-ity名词后缀;’升起”→飘起→飘浮] 轻浮，轻率