Simple past tense and past participle of humidify.(verb)
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Use "humidified" in a sentence
"The Magna Carta was then humidified, flattened and will lie untouched for at least three months under weights to reach the proper moisture level before being placed in a new case with humidified, inert gas for long-term preservation."
"By that, I refer to my life routine -- from what I eat to what I drink and don't drink -- alcohol! to the eye drops and ointments that I insert, to the humidified rooms I inhabit, to the moisturizer and makeup I apply."