Someone who is incredibly clumsy; a clumzie.
Said person may be a bit of an airhead and may also forget to think before speaking.
(After someone trips)... "Gosh, you're such a finkels!"
(After someone drops something)... "Why don't you just change your name to finkels, huh?!"
(After someone asks a really stupid question)... "That was soo finkels of you!"