1. flake out change from a waking to a sleeping state
  2. walk out leave suddenly, often as an expression of disapproval
  3. walkout the act of walking out as a sign of protest
  4. flare out become flared and widen, usually at one end
  5. flame-out the failure of a jet engine caused by an interruption of the fuel supply or by faulty combustion
  6. flat out at top speed
  7. flake off come off in flakes or thin small pieces
  8. flecked having a pattern of dots
  9. walkabout a walking trip or tour
  10. flageolet a French bean variety with light-colored seeds
  11. Flag Day commemorating the adoption of the United States flag in 1777
  12. flout treat with contemptuous disregard
  13. flat coat the first or preliminary coat of paint or size applied to a surface
  14. flagitious extremely wicked, deeply criminal
  15. flagroot perennial marsh plant having swordlike leaves and aromatic roots
  16. flagellate whip or scourge; punish as if by whipping
  17. freak out lose one's nerve
  18. blackout darkness resulting from the extinction of lights
  19. flesh out add details, as to an account or idea
  20. black out darken completely