What is the plural form of 'lumen'?

The plural form of 'lumen' is 'lumina.' This term originates from Latin, where many medical and scientific terms retain their Latin roots. In Latin, nouns that end in "-um," like 'lumen,' typically change to "-a" for their plural forms, thus 'lumen' in singular becomes 'lumina' in plural.

The other options do not correctly follow this linguistic rule. 'Lumens' is commonly used in English, particularly in contexts like lighting, but it is not the correct classical plural in the context of anatomy or medicine. 'Lumins' and 'lumenes' are not recognized forms and do not align with the established conventions of Latin-derived medical terminology. Thus, 'lumina' is the accurate pluralization of 'lumen.'