English to English

noun (n)

• an unforeseen or unexpected or surprising difficulty(noun.cognition)

  Synonym:
  booby trap
  

  source: wordnet30
• a trap in the form of a concealed hole(noun.artifact)

  Synonym:
  pit
  

  source: wordnet30
• A pit deceitfully covered to entrap wild beasts or men; a trap of any kind.(noun)

  source: webster1913