Non is defined as not or no.(prefix)
An example of non used as a prefix is in the phrase, "non-essential," which means not essential.
Non is defined as no.(interjection)
An example of non used as an interjection is in the sentences, "Non! I don't want to go to the park today!" which means "No! I don't want to go to the park today!"
See non in Webster's New World College Dictionary
Origin: < L non, not < OL noenum < ne-, negative particle (see no) + oinom, one
See non in American Heritage Dictionary 4
Origin: Middle English
Origin: , from Old French
Origin: , from Latin nōn, not; see ne in Indo-European roots.
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