Is it especial or special?

The adjectives special and especial are synonyms. However, “especial” is used much less frequently than “special,” has a formal effect in modern English, and can only be used before a noun (i.e., you can’t use it as a predicate adjective). So, you can say “a special treat” and “an especial treat,” but not “the treat was very especial.”

On a related note, if you’re having difficulty deciding whether especially or specially is the word you need, we typically use “specially” with “made,” “built,” etc. to mean “specifically” (e.g., “I had it specially made”).

Have you tried QuillBot’s free Grammar Checker? It can pick up errors such as “especial” used predicatively rather than attributively.