"The cult and practice of going unclothed" [OED], 1929, from French nudisme (see nude + -ism). Nudist "one who practices nudism" appeared at the same time.
Made in Germany, imported to France, is the cult of Nudism, a mulligan stew of vegetarianism, physical culture and pagan worship. ["Time," July 1, 1929]
nudge
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nudibranch
nudie
nudification
nudism
nudist
nudity
nudnik
nuff
nugatory
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