The word "disallow" means to refuse to accept or to reject. Its antonyms, therefore, are words that mean the opposite: to allow, permit, or authorize. Some common antonyms of "disallow" include "approve," "accept," "sanction," "endorse," "consent," "bless," "authorize," and "ratify." The use of an antonym depends on the context of the sentence or situation. If we want to say that something is allowed, we could use any of these words to communicate that idea. In contrast, if something is not allowed, the word "disallow" would be appropriate.