Definition of "puerility"

puerility

noun
countable and uncountable, plural puerilities
1. The state, quality, or condition of being childish or puerile.
  Quotations
  This classification should have led to the discovery and study of remedies which act specifically upon the various textures and tissues of the body, such as the cellular, serous, mucous, parenchymatous, fibrous, gelatinous, &c., but it did not, except in the most imperfect manner—so imperfect, in fact, that most pathologists, despairing of finding such remedies, at one time sank into all the peurilities[sic – meaning puerilities] of the "expectant mode" of the French, or the nihilisms of the German.
  1863, John C. Peters, F[rederick] G. Snelling, “Section I. Of Medicine as a Science and as an Art; Its Objects and Its Extent.”, in Principles and Practice of Medicine, New York, N.Y.: William Radde, […], page 124
2. That which is puerile or childish; especially, an expression which is insipid or silly.
  Quotations
  You treat his opinions (though he never thrusts them on you) about "the Church," and his duty, and the souls of his parishioners, with civil indifference, as much ado about nothing; and his rubrical eccentricities as puerilities.
  1857, Charles Kingsley, “The Way to Win Them”, in Two Years Ago, volume I, Cambridge, Cambridgeshire: Macmillan and Co., page 140