What kind of context may be applied to the use of ‘rarefied’?

One can employ ‘rarefied’ to denote something that is elevated and is in some ways acquiring a superior, or refined characteristic and there’s nothing wrong with ‘rarefied’ air or ‘rarefied’ club of scholars.

Can 'robotic' be used to describe human behavior?

Yes, it's possible to apply the adjective ‘robotic’ to human behavior, which people designate as being stiff, cold and non-expressive, as well as mechanical and automatic in nature, as far as the emotions are concerned.

Can you provide examples of 'rakish' behavior?

The term rakish denotes a somewhat stylish and assured attitude with a touch of allure, for instance, an individual who walks and may even dress heavy and possibly exhibit selfish risky actions possibly in the dressing code of conduct.