Butterfingers

Etymology
From butter (a slippery substance) + finger

Noun

 * 1) someone who is clumsy or uncoordinated; a klutz; someone who tends to drop things
 * I am such a butterfingers. That's the third drink I've spilled today.

Thesaurus
clumsy, dub, duffer, foozler, foul-up, fumble-fist, goof, goofball, goofer, hick, lummox, lump, muff, muffer, rube, slob, stumblebum, stumblebunny