Table 2.

Latin plural endings in English medical terminology

Singular	Plural	Singular	Plural
Vertebra	Vertebrae	Bacillus	Bacilli
Atrium	Atria	Bronchus	Bronchi
Bacterium	Bacteria	Focus	Foci
Curriculum	Curricula	Fungus	Fungi
Datum	Data	Nucleus	Nuclei
Dorsum	Dorsa	Stimulus	Stimuli
Erratum	Errata	Analysis	Analyses
Labium	Labia	Apex	Apices
Medium	Media	Appendix	Appendices
Septum	Septa	Axis	Axes
Stratum	Strata	Crisis	Crises
Symposium	Symposia	Diagnosis	Diagnoses
Criterion	Criteria	Index	Indices
Ganglion	Ganglia	Paralysis	Paralyses
Phenomenon	Phenomena	Thesis	Theses

To facilitate memorization, Latin terms are grouped on the basis of their declension and gender