| Term | Definition |
| a cappella | "in the manner of the chapel". Music sung without instrumental accompaniment |
| a tempo | return to the original tempo after some deviation |
| accelerando | becoming faster |
| accidentals | symbols used to raise or lower a pitch by one or two semi-tones, or to cancel a previous sign or part of a key signature |
| adagio | slow leisurely tempo |
| al fine | to the end, generally used after a repetition |
| alla breve | a tempo marking indicating quick double time i.e. 2/2 instead of 4/4 with the half note rather than the quarter note as the beat |
| allegretto | slightly slower than allegro, often implying lighter texture and character as well |
| allegro | fast |
| allegro con spirito | fast tempo with spirit |
| amabile | sweet, lovable |
| ancora meno mosso | once more but a little slower |
| andante | rather slow, at a moderate walking pace |
| aria | a self-contained composition for solo voice, usually with instrumental accompaniment and usually found within the context of an opera, oratorio, or cantata |
| arpeggio | a broken chord |
| atonal | music that lacks a tonal center; absence of key |
| augmented | raised or enlarged. generally refers to the raising of a pitch by one half step |
| ballad | a strophic narrative song |
| berceuse | a lullaby |
| cadenza | an improvised or written out ornamental passage preformed by a soloist usually near the final cadence |