The Greek word "koios" commonly translates to "who" or "which" in English, but there are many other synonyms that can be used depending on the context. Some of these synonyms include "what", "whom", "whose", "whatever", "whichever", and "whoever". Each of these words can be substituted for "koios" in a sentence, allowing for more variety and nuance in language. Choosing the appropriate synonym can help clarify the meaning of a sentence and add depth to its expression. For example, using "whose" instead of "which" can indicate possession or ownership, while using "whoever" can suggest a sense of inclusivity and openness.