| ademanes | gesticulation |
| Ademar de Monteil | Adhemar of Le Puy |
| Ademir Marques de Menezes | Ademir Marques de Menezes |
| ademán | motion |
| además | besides |
| además de | apart from |
| Aden Abdullah Osman Daar | Aden Abdullah Osman Daar |
| adenectomía | adenectomy |
| Adenet Le Roi | Adenet Le Roi |
| Adenilato ciclasa | Adenylate cyclase |
| Adenilato kinasa | Adenylate kinase |
| adenina | adenine |
| adenitis | adenitis |
| Adenium | Adenium |
| Adenocalymna | Adenocalymna |
| adenoide | adenoid |
| adenoidectomía | adenoidectomy |
| adenoides | adenoids |
| adenosina | adenosine |
| Adenosín difosfato | Adenosine diphosphate |
| Adenosín monofosfato cíclico | Cyclic adenosine monophosphate |
| Adenosín trifosfato | Adenosine triphosphate |
| Adenoviridae | Adenoviridae |
| Adenovirus | Adenoviridae |
| adentrarse | dig into |
| Adentrarse en | Get inside |
| adentro | in |
| adentro de la casa | inside the house |
| Adeodato I | Pope Adeodatus I |
| Adeodato II | Pope Adeodatus II |
| ADEOS | Adaptive Domain Environment for Operating Systems |
| Adephaga | Adephaga |
| Adept | Adept Manager |
| adepto | adept |
| Ader | Vein |
| Aderbal | Ad Herbal |
| Aderbal de Numidia | Ad Herbal |
| aderezo | dressing |
| aderezo de ensalada | salad dressing |
| Adeste Fideles | Adeste Fideles |
| adeudar | arrears |
| Adewale Akinnuoye-Agbaje | Adewale Akinnuoye-Agbaje |
| adhan | adhan |
| Adhara | Epsilon Canis Majoris |
| Adhemar Ferreira da Silva | Adhemar da Silva |
| adherencia | adhesion |
| Adherencia celular | Cell adhesion |
| adherente | adherent |
| adherible | sticky |
| adherir | attach |
| adherirse | connect |
| adherirse a | profess |
| adhesividad | clinging |
| adhesivo | adherent |
