"Most cosmos" is a phrase that implies something is very cosmopolitan or worldly. Some synonyms for this phrase could include "urbane", "cultured", "sophisticated", or "cosmopolitan". These words all suggest a level of refinement or refinement that is associated with an understanding of and appreciation for different cultures, ideas, and experiences. Other synonyms might include "worldly" or "well-traveled", which suggest that someone has experienced a variety of cultural influences and has a broad perspective on the world. Whatever words you choose, they all suggest a sense of openness and curiosity about what lies beyond one's own immediate surroundings, and a willingness to engage with new and different ideas.