1. breakthrough the act of making an important discovery
  2. progenitor an ancestor in the direct line
  3. break through pass through (a barrier)
  4. bring through bring into safety
  5. prognathous having a projecting lower jaw
  6. broken-down not in working order
  7. broken heart devastating sorrow and despair
  8. breeze through succeed at easily
  9. work through apply thoroughly; think through
  10. run through use up (resources or materials)
  11. Bruckenthalia a genus containing only one species: spike heath
  12. run-through an uninterrupted rehearsal
  13. brown thrush common large songbird of eastern United States having reddish-brown plumage
  14. raconteur a person skilled in telling anecdotes
  15. brokenhearted full of sorrow
  16. prognathic having a projecting lower jaw
  17. Perognathus pocket mice
  18. broken arch an arch with a gap at the apex
  19. broken home a family in which the parents have separated or divorced
  20. through having finished or arrived at completion