a flat plate that controls or directs the flow of fluid or energy
be a mystery or bewildering to; "This beats me!"; "Got me--I don't know the answer!"; "a vexing problem"; "This question really stuck me"
hinder or prevent (the efforts, plans, or desires) of; "What ultimately frustrated every challenger was Ruth's amazing September surge"; "foil your opponent"
restrain the emission of (sound, fluid, etc.)