If you describe a person, animal, or vehicle as ungainly, you mean that they look awkward or clumsy, often because they are big. The dog, an ungainly mongrel pup, was loping about the road Paul swam in his ungainly way to the side of the pool. = clumsy. moving in a way that does not look graceful (gainly (14-20 centuries), from gain (10-19 centuries), from gegn)
difficult to handle or manage especially because of shape; "an awkward bundle to carry"; "a load of bunglesome paraphernalia"; "clumsy wooden shoes"; "the cello, a rather ungainly instrument for a girl"
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"