Some dogs are small. They are pets.
dog duck (weird pet) dove ^^
Dot, Daisy, Doo-Doo,
· diminutive
Dormitory is a type of structure. It begins with the letter d.
dog
A Door mouse
diplodocus
· daffodil · dahlia · daisy · dandelion
Duesenberg, Dodge, Daewoo, DeLorean
De Brazza's monkey
Durum is a type of wheat, if that helps.
A duiker is an example of an animal that starts with a "d" and has six letters. It is a small antelope found in sub-Saharan Africa.