"Khi" is a Vietnamese word that translates to "air" or "atmosphere" in English. Some synonyms for this word are "không khí" which means "air" or "atmosphere" as a noun, or "khí quyển" which translates to "atmosphere" or "air surrounding the Earth". Another synonym for "khi" is "khí hậu" which means "climate" or "weather". In a more poetic sense, "khi" can be replaced with "cánh trời" which means "sky" or "heavens". Overall, these synonyms for "khi" help to illustrate the various shades of meaning and contexts in which the word can be used in Vietnamese language and culture.