acute  
English
Technical (English): acute
Popular (English): severe
Spanish
Technical: agudo (adj)
Popular: súbito y breve

---

anaphylactic  
English
Technical (English): anaphylactic
Popular (English): severe allergic response-related
Spanish
Technical: anafiláctico (adj)
Popular: relativo a una reacción alérgica general violenta

---

aplastic anaemia  
English
Technical (English): aplastic anaemia
Popular (English): severe anaemia
Spanish
Technical: anemia (nf) aplástica
Popular: formación insuficiente de células de la sangre

---

obstipation  
English
Technical (English): obstipation
Popular (English): severe constipation
Spanish
Technical: constipación (nf)
Popular: estreñimiento (nm)

---

polyarthritis  
English
Technical (English): polyarthritis
Popular (English): severe arthritis
Spanish
Technical: poliartritis (nf)
Popular: inflamación de varias articulaciones simultáneamente

---

SARS (Severe Acute Respiratory Syndrome)  
English
Technical (English): SARS (Severe Acute Respiratory Syndrome)
Popular (English): SARS (Severe Acute Respiratory Syndrome)
Spanish
Technical: SARS (Síndrome Agudo Respiratorio Severo)
Popular: SARS (Síndrome Agudo Respiratorio Severo)

---

severe  
English
Technical (English): severe
Popular (English): severe
Spanish
Technical: grave, intenso, fuerte
Popular: grave, intenso, fuerte

---