different between puerility vs lunacy

English

Etymology

puerile +? -ity, from Middle French puérilité, from Latin puer?lit?s, from puer?lis (“childish, juvenile”), from puer (“boy”).

Noun

puerility (countable and uncountable, plural puerilities)

1. The state, quality, or condition of being childish or puerile.
2. That which is puerile or childish; especially, an expression which is insipid or silly.
   • 1857, Charles Kingsley, Two Years Ago

     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.

See also

• puerilism

English

Etymology

From lunatic +? -cy.

Pronunciation

• (UK) IPA^(key): /?lu?.n?.si /, /?lju?.n?.si/
• (US) IPA^(key): /?lu?.n?.si /

Noun

lunacy (countable and uncountable, plural lunacies)

1. (of a person or group of people) The state of being mad, insanity
   1. a cyclical mental disease, apparently linked to the lunar phases
   2. insanity implying legal irresponsibility.
2. Something deeply misguided.

Synonyms

• (state of being mad): insanity, madness, craziness, craze

Translations