| Term | Definition |
| abate | subside or moderate |
| aberrant | abnormal or deviant |
| abeyance | suspended action |
| abscond | depart secretly and hide |
| abstemious | sparing in eating and drinking; temperate |
| admonish | warn; reprove |
| adulterate | make impure by adding inferior or tainted substances |
| aesthetic | artistic; dealing with or capable of appreciating the beautiful |
| aggregate | gather; accumulate |
| alacrity | cheerful promptness; eagerness |
| alleviate | relieve |
| amalgamate | combine; unite in one body |
| ambiguous | unclear or doubtful in meaning |
| ambivalence | the state of having contradictory or conflicting emotional attitudes |
| ameliorate | improve |