1. antiseptic - Anything that destroys or restrains the growth of putrefactive micro-organisms.
2. antislavery - Opposed to human slavery.
3. antispasmodic - Tending to prevent or relieve non-inflammatory spasmodic affections.
4. antistrophe - The inversion of terms in successive classes, as in "the home of joy and the joy of home".
5. antitoxin - A substance which neutralizes the poisonous products of micro-organisms.
6. antonym - A word directly opposed to another in meaning.
7. anxious - Distressed in mind respecting some uncertain matter.
8. apathy - Insensibility to emotion or passionate feeling.
9. aperture - Hole.
10. apex - The highest point, as of a mountain.
11. aphorism - Proverb.
12. apiary - A place where bees are kept.
13. apogee - The climax.
14. apology - A disclaimer of intentional error or offense.
15. apostasy - A total departure from ones faith or religion.