| A | B |
| auto- | prefix meaning "self" |
| contra-/contro- | prefix meaning "against" |
| autobiography | the story of a person's life written by that person |
| autograph | a person's signature |
| automatic | having a self-acting or self-regulating mechanism |
| controversy | a difference of opinion that lasts a long time about an important matter |
| autonomous | self-governing |
| contraband | any articles forbidden to be brought into or taken out of a country |
| contradict | to say the opposite |
| contrary | opposite or opposed |
| contrast | to compare by showing differences |
| automobile | a passenger vehicle with its own engine |