Nonplus is a state of confusion where you don't know what to do, think or say.(noun)
An example of nonplus is being told to turn right on Fifth Street while approaching the intersection where North Fifth Street is to the left and South Fifth Street is to the right.
See nonplus in Webster's New World College Dictionary
Origin: L non, not + plus, more: see plus
See nonplus in American Heritage Dictionary 4
transitive verb non·plussed also non·plused, non·plus·sing also non·plus·ing, non·plus·ses also non·plus·es
Origin: From Latin nōn plūs, no more
Origin: : nōn, not; see non-
Origin: + plūs, more; see pelə-1 in Indo-European roots.
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