the mind > emotion > excitement > excitability of temperament > spiritedness or liveliness > [noun] > mercurial spirits (6)
The condition of being mercurial; liveliness, volatility; an instance of this.
figurative. Spirit, liveliness; volatility of temperament, inconstancy; wittiness. Obsolete.
Mercurial quality; liveliness, sprightliness; volatility.