nonplused

Adjective

nonplussed (comparative more nonplussed, superlative most nonplussed)

1. Unsure how to act or respond; bewildered, perplexed.
   • [N]ote the honeſt Quaker vvas nonpluſſed, and greatly ſurprized at that Queſtion.1724, [Daniel Defoe], The Fortunate Mistress; […] [Roxana], London: […] E. Applebee, […], published 1740, →OCLC, page 277

   Synonyms:

   confounded, vexed, lost for words, addle-pated, addled, addlepated, at a loss, at a loss for words, at sea, at sixes and sevens

   Antonyms:

   plussed

2. (US, informal, nonstandard) Unaffected, unfazed; unimpressed.
   • "I regard Dean [W. P.] Baddeley's gambling activities with embarrassment and dismay," said Anglican dean of Melbourne S. Barton Babbage. […] The Rev. Baddeley remained nonplussed. "I don't intend to make a habit of going to the races but I feel clergymen should mix as our Lord did with all walks of...1960 August 2, “Cleric’s error was to win his wagers”, in Oakland Tribune, home edition, volume CLXXIII, number 33, Oakland, Calif.: Oakland Tribune, →ISSN, →OCLC, page E7, column 6

   Synonyms:

   blasé, jaded, adiaphroistic, apathetic, apathistical, blithe, deaf, cool, shiftless, dispassionate

   Antonyms:

   plussed

Verb

nonplus (third-person singular simple present nonplusses or nonpluses, present participle nonplussing or nonplusing, simple past and past participle nonplussed or nonplused)

1. (transitive) To bewilder or perplex (someone); to confound, to flummox.
   • You couldn’t have told it from my manner, but I was feeling more than a bit nonplussed. The spectacle before me was enough to nonplus anyone.1934 October 5, P[elham] G[renville] Wodehouse, chapter II, in Right Ho, Jeeves, London: Herbert Jenkins […], →OCLC, page 24

See all 2 meanings of nonplus