Look up a- in Wiktionary, the free dictionary.
A- or a- may refer to:
- A-hyphen
- A- (plane), a U.S. military aircraft prefix
- Privative a, a prefix expressing negation
- Copulative a, a prefix expressing unification
- A-minus
- A−, a blood type
- A− (grade), an educational grade in the letter-grading system, above B+ but below A
