Are the words CONSUMABLES and DISPOSABLES synonyms and if so why dictionaries don't say so?

Answer 1

"Consumables" is short for "consumable goods" and "disposables" is short for "disposable goods." Consumable means able to be consumed, and disposable means suitable for disposal. That is, you can use consumable goods, which get used up in the process. Disposable goods, on the other hand, can be thrown out. If you buy an electronic product in the store, it will likely come encased in plastic and Styrofoam which is useless and has to be thrown out. It is disposable. It is not consumable, because you cannot use it.

Answer 2

The two words are not synonymous; and if they were, the dictionary would not necessarily say so.