A waddler is someone or something that waddles, which means walking with short steps while swaying from side to side. Picture a penguin making its way across the ice, rocking left and right with each step, or a toddler in a full diaper taking those unsteady, wobbly steps across the living room.

The waddle happens because of body shape or balance. Penguins waddle because their legs are short and positioned far back on their bodies, perfect for swimming but awkward for walking on land. Ducks waddle for similar reasons. A two-year-old waddles because they're still learning to balance and their proportions are different from older kids: big head, short legs, round middle.

When you call someone a waddler, you're usually describing their walk in an affectionate or humorous way. Parents might lovingly call their toddler “our little waddler” as they watch those cute, clumsy first steps. You might see someone carrying heavy grocery bags in both hands, swaying side to side as they walk, and think they look like a waddler.

The word captures both the movement and the charming awkwardness of it. Nobody waddles elegantly: it's inherently a bit clumsy, a bit funny, and often endearing to watch.