question marks

Noun

question mark (plural question marks)

1. The punctuation mark "?", used at the end of a sentence to indicate a question.
   • Do you see this curious-looking mark in the margin? It is a little crooked mark with a dot at the bottom of it. It is a question mark. It always comes at the end of questions.1856, Jacob Abbott, “Lesson V. Questions.”, in Learning to Read. […] (Harper’s Picture Books for the Nursery; The Little Learner), New York, N.Y.: Harper & Brothers, […], →OCLC, part III (Hard...

   Synonyms:

   interrogation mark, interrogation point, query, eroteme, interrogative, interrogative-point, note of interrogation, mark of interrogation

2. (figuratively, informal) A state of doubt or uncertainty.
   • There’s a question mark over whether or not he’ll be fit for the next game.
3. (figuratively, informal) An enigmatic, inscrutable, or mysterious person or thing; an enigma, a riddle.
   • Let us admit that the Platonic dialogue is an enigma—something perplexing and to be wondered at. The Platonic dialogue is one big question mark.1964, Leo Strauss, “On Plato’s Republic”, in The City and Man, paperback edition, Chicago, Ill.; London: University of Chicago Press, published 1978, →ISBN, page 55

   Synonyms:

   mystery, puzzle

4. Polygonia interrogationis, a North American nymphalid butterfly with a silver mark on the underside of its hindwing resembling a question mark (sense 1).
   • Question Mark (Polygonia interrogationis). Preferred host plants are elms (Ulmus spp.), hackberry (Celtis spp.), hops (Humulus spp.), nettle (Urtica spp.), and false nettle (Boehmeria cylindrica).1990, Wendy Potter-Springer, “List of Host Plants for Caterpillars”, in Heather Clemow, editor, Grow a Butterfly Garden (A Storey County Wisdom Bulletin; A-114), North Adams, Mass.: Storey...

See all 5 meanings of question mark