Medical Terminology / Unit 1 MedTerm 0038 short lesson, about 20 seconds
Plural Rule: us Becomes i
Captions available
The idea
A singular ending in u s forms its plural by changing the u s to i.
In practice
Bronchus becomes bronchi; nucleus becomes nuclei; alveolus becomes alveoli.
Where people slip
Virus and sinus are exceptions. Virus takes viruses; sinus takes either sinuses or the unchanged sinus.
Your place on the trail
Every lesson rests on earlier ones and opens later ones. Tap any to jump.
Something wrong in this lesson? Flag it · Sources for Medical Terminology