ungainly
Moving in a clumsy, awkward, and not very graceful way.
Ungainly means moving in an awkward, clumsy way that looks uncomfortable or uncoordinated. Picture a baby giraffe taking its first wobbly steps, or imagine trying to walk across a room while wearing flippers: those movements would be ungainly.
The word usually describes physical movement, but it can also describe objects that look awkward or poorly designed. An ungainly piece of furniture might be too large for its room, bumping into corners and making the space feel cramped. An ungainly backpack might be so stuffed with books that it throws off your balance when you wear it.
What makes something ungainly is that the thing or person hasn't quite figured out how to manage their size or shape yet. A Great Dane puppy with huge paws stumbling over itself is ungainly. A skilled basketball player, even if they're very tall, moves with grace and wouldn't be called ungainly.
The opposite of ungainly would be graceful, smooth, or coordinated. Everyone feels ungainly sometimes, like when you're learning a new sport or going through a growth spurt. The good news is that most ungainly phases pass with practice and time.