Strong's #5156: tromos (pronounced trom'-os)
 from 5141; a "trembling", i.e. quaking with fear:--+ tremble(-ing).
Thayer's Greek Lexicon:
 ́ 
 
  tromos 
 
 1) a trembling or quaking with fear
 2) with fear and trembling, used to describe the anxiety of one who distrusts his ability completely to meet all requirements, but religiously does his utmost to fulfil his duty
 
  Part of Speech: noun masculine
Relation: from G5141
 
Usage:
This word is used 5 times:
Mark 16:8: "sepulcher; for they  trembled and were amazed: neither"
1 Corinthians 2:3: "and in much  trembling."
2 Corinthians 7:15: "with fear and  trembling ye received him."
Ephesians 6:5: "with fear and  trembling, in singleness of your heart,"
Philippians 2:12: "with fear and  trembling."