Seneca, On Benefits
2.34.2 (tr. John W. Basore):
There is a vast number of things that have no name, and the terms by which we designate them, instead of being their own, belong to other things from which they are borrowed. We say that we ourselves, a couch, a sail, and a poem, have a "foot," and we apply the word "dog" to a hound, to a creature of the sea, and to a constellation; since there are not enough words to make it possible for us to assign a separate one to each separate thing, we borrow whenever it becomes necessary.
ingens copia est rerum sine nomine, quas non propriis appellationibus notamus, sed alienis commodatisque. pedem et nostrum dicimus et lecti et veli et carminis, canem et venaticum et marinum et sidus; quia non sufficimus, ut singulis singula adsignemus, quotiens opus est, mutuamur.