snag vs stumbling block

snag

noun
  • A problem or difficulty with something. 

  • A stump or base of a branch that has been lopped off; a short branch, or a sharp or rough branch. 

  • A sausage. 

  • A tooth projecting beyond the others; a broken or decayed tooth. 

  • A goal. 

  • A misnaged, an opponent to Chassidic Judaism (more likely modern, for cultural reasons). 

  • A dead tree that remains standing. 

  • A tree, or a branch of a tree, fixed in the bottom of a river or other navigable water, and rising nearly or quite to the surface, by which boats are sometimes pierced and sunk. 

  • Any sharp protuberant part of an object, which may catch, scratch, or tear other objects brought into contact with it. 

  • A pulled thread or yarn, as in cloth. 

  • One of the secondary branches of an antler. 

verb
  • To obtain or pick up. 

  • To damage or sink (a vessel) by collision; said of a tree or branch fixed to the bottom of a navigable body of water and partially submerged or rising to just beneath the surface. 

  • To cut the snags or branches from, as the stem of a tree; to hew roughly. 

  • To fish by means of dragging a large hook or hooks on a line, intending to impale the body (rather than the mouth) of the target. 

  • To catch or tear (e.g. fabric) upon a rough surface or projection. 

stumbling block

noun
  • A hindrance, obstacle or impediment; an opportunity for error. 

How often have the words snag and stumbling block occurred in a corpus of books? (source: Google Ngram Viewer )