The letters 'a', 'e', 'o', 'r', 's', and 't' have already been guessed. The current word pattern shows that 'o' and 'a' are in the correct positions, while 'r' is also revealed. Based on common words that fit the pattern 'or__ar_', the letter 'n' seems a likely candidate to complete the word. Words like 'orange' or 'ornar' could potentially fit.