We told you about ʻelemakule, which means old man, and today's Hawaiian Word of the Day is luahine, or old woman. It can also mean old lady. Both are proper terms, and it is perfectly all right to describe our older friends as ʻelemakule and luahine.
Makua is a very general term for parent, or any relative of the parent's generation, as in an uncle or aunt. Since the main stock of a plant is thought of as the parent, you can also call it a makua. You can modify it to be more specific, as makua kāne for father.