Synonyms: poser, toughie, sticker, stumper
Definition: a particularly difficult or baffling question or problem
Similar words: problem
Definition: a question raised for consideration or solution
Usage: our homework consisted of ten problems to solve
Definition: a person who poses for a photographer or painter or sculptor
Usage: the president didn't have time to be a model so the artist worked from photos
Similar words: assistant, help, helper, supporter
Definition: a person who contributes to the fulfillment of a need or furtherance of an effort or purpose
Usage: my invaluable assistant; they hired additional help to finish the work
Definition: a person who habitually pretends to be something he is not
Similar words: show-off, exhibitionist
Definition: someone who deliberately behaves in such a way as to attract attention