Wordnet 3.0
ADJECTIVE (2)
1. 
 lacking grace in movement or posture; 
- Example: "a gawky lad with long ungainly legs"- Example: "clumsy fingers"- Example: "what an ungainly creature a giraffe is"- Example: "heaved his unwieldy figure out of his chair"[syn: gawky, clumsy, clunky, ungainly, unwieldy]
2.  making a clunking sound; 
WordNet (r) 3.0 (2006):
clunky
    adj 1: lacking grace in movement or posture; "a gawky lad with
           long ungainly legs"; "clumsy fingers"; "what an ungainly
           creature a giraffe is"; "heaved his unwieldy figure out
           of his chair" [syn: gawky, clumsy, clunky,
           ungainly, unwieldy]
    2: making a clunking sound