Expansion of medical Latin abbreviation (ventric. later. dextr.)

Question

I don't know enough Latin grammar to properly expand this abbreviation: ventric. later. dextr.

I am aware that it means the right lateral ventricle in the brain, the lateral ventricles as a whole being called ventriculi lateri, but that's obviously plural.

So, what is the correct full phrasing for specifically the right-side one? Ventriculus laterus dextrus?

Answer 1

Close! Lateralis ("lateral") is a third-declension adjective, so it takes the ending -is instead of -us for this form. Similarly, dextr. is actually dexter, not dextrus: it's one of the odd adjectives that end in R in the masculine nominative singular.

So all together, this would be the ventriculus lateralis dexter: the right lateral ventricle.

(The plural should likewise be ventriculi laterales, not lateri, in Classical Latin; Google suggests this is true in medical terminology as well.)