puzzle

головоло́мка

Often preceded by a descriptive word: a game or toy, or a problem, requiring some effort to complete or work out, which is intended as a pastime and/or to test one's mental ability

• This puzzle is easy to solve.

  Эта загадка легко решается.

  Tatoeba · araneo · CC BY 2.0 FR

• No one could solve the puzzle.

  Никто не смог разгадать загадку.

  Tatoeba · CK · CC BY 2.0 FR

головоло́мка

The state of feeling confused or mystified because one cannot understand a complicated matter, a problem, etc.; bewilderment, confusion; (countable) often in in a puzzle: an instance of this

головоло́мка

A thing such as a complicated matter or a problem which is difficult to make sense of or understand; also, a person who is difficult to make sense of or understand; an enigma