Which word characterizes someone with a proud and contemptuous attitude?

The word "supercilious" is characterized by an attitude that is both proud and contemptuous. When someone is described as supercilious, it implies that they have a sense of superiority over others, often looking down upon them with disdain or scorn. This attitude is often visible in body language and demeanor, where the individual might exude confidence that borders on arrogance.

In contrast, the other words do not carry the same connotation. "Nonchalant" describes a person who is casually unconcerned or indifferent, lacking the proud or disdainful attributes. "Omniscient" refers to an all-knowing perspective, which does not inherently express pride or contempt. Lastly, "invulnerable" suggests being impervious to harm or incapable of being wounded, which does not relate to a social attitude or demeanor. Therefore, supercilious genuinely captures the essence of someone who carries a proud and dismissive view of others.