frothiness

a lack of seriousness often at an improper time try to restrain your natural frothiness at least for the duration of the lecture Synonyms facetiousness, flightiness, flippancy, frivolousness, frivolity, levity, light-headedness, light-mindedness, lightness, sillinessRelated Words cheer, cheerfulness, festivity, gaiety (also gayety), glee, gleefulness, high-spiritedness, hilarity, joviality, lightheartedness, merriment, mirth, mirthfulness; childishness, goofiness, puerilityNear Antonyms dejection, depression, despondency, dispiritedness, downheartedness, gloom, gloominess, heartsickness, joylessness, melancholy, mopes, moroseness, sadness, sullenness, unhappinessAntonyms earnestness, gravity, seriousness, soberness, solemnity, solemnness