| a-, an- | No, lacking, none |
| ab- | Away from, out from |
| abyss- | Deep, bottomless |
| ac- | To, toward |
| -aceus, -aceous | Of or pertaining to |
| acou- | Hearing |
| acr-, acro- | Extreme, peak |
| actin- | A ray, spoke |
| ad- | To, toward |
| adeno- | Gland |
| aero- | The air |
| agri- | Field, soil |
| -al | Having character of |
| alb- | White |
| -alexi | To ward off |
| -algia | Pain |
| allo- | Other, different |
| alto- | High |
| ambi- | On both sides |
| ameb- | Change, alteration |
| amphi-, ampho-, amb- | Leading a double life, both |
| an- | Not, without |
| ana- | Up |
| andro- | Masculine, man |
| anemo- | Wind |
| angio- | Vessel |
| ante- | Before, ahead of time |
| antero- | Front |
| anth- | Flower |
| anthropo- | Man |
| anti- | Against |
| ap- | To, toward |
| apic- | Tip, end |
| apo- | Off, away |
| -apsis | Juncture |
| aqu- | Water |
| arachn- | A spider |
| arch- | Primitive, ancient |
| arthro- | Joint |
| aster-, astr- | Stars |
| atom- | Vapor |
| audi- | Hear |
| auto- | Self |
| aux- | Grow, enlarge |