The Collaborative International Dictionary of English v.0.48:
Waddle \Wad"dle\, v. i. [imp. & p. p. Waddled; p. pr. & vb. n.
Waddling.] [Freq. of wade; cf. AS. w[ae]dlian to beg, from
wadan to go. See Wade.]
To walk with short steps, swaying the body from one side to
the other, like a duck or very fat person; to move clumsily
and totteringly along; to toddle; to stumble; as, a child
waddles when he begins to walk; a goose waddles. --Shak.
She drawls her words, and waddles in her pace. --Young.