Word: 
Similar-sounding words in the dictionary:
3 letters:
duc, duk, dux
4 letters:
duck, dust, dutt
5 letters:
ducks, ducts, lucht
6 letters:
bucked, decked, docked, duck's, ducker, ducks', dunked, sucked, tucked, ducked
7 letters:
chucked, duckett, shucked