1. master class a class given to talented students by an expert
  2. best of all especially fortunate
  3. 1st class mail that includes letters and postcards and packages sealed against inspection
  4. pane of glass sheet glass cut in shapes for windows or doors
  5. soft glass glass having a relatively low softening point
  6. Feast of Weeks (Judaism) Jewish holy day celebrated on the sixth of Sivan to celebrate Moses receiving the Ten Commandments
  7. reserve clause a clause that used to be part of the contract with a professional athlete extending the contract for a year beyond its expiration
  8. pestiferous contaminated with infecting organisms
  9. relative clause a clause introduced by a relative pronoun
  10. boastfulness outspoken conceit
  11. port of call any port where a ship stops except its home port
  12. suit of clothes a set of garments (usually including a jacket and trousers or skirt) for outerwear all of the same fabric and color
  13. postfix an affix that is added at the end of the word
  14. plate glass glass formed into large thin sheets
  15. first-class very good;of the highest quality
  16. osteoclast cell that functions in the breakdown and resorption of bone tissue
  17. osteoclasis treatment of a skeletal deformity by intentionally fracturing a bone
  18. senior class final grade or class in high school or college
  19. peace advocacy any policy that advocates maintaining peaceful international relations
  20. pontifical proceeding from or ordered by or subject to a pope