"Dull of eye" is a phrase used to describe someone who appears tired, bored, or uninterested. There are many different ways to describe this appearance using synonyms.
For example, one could use the phrase "heavy-lidded" to describe someone whose eyelids appear droopy or weighed down. Another option is to use the word "listless," which suggests a lack of energy or enthusiasm. "Lackluster" is another alternative, which describes something that lacks brightness or shine.
One could also use words like "blunted," "lethargic," or "apathetic" to describe someone who appears dull of eye. Additionally, words like "uninspired" or "unfocused" could also be used to describe someone who appears uninterested or bored.
Overall, there are many different ways to describe someone who appears dull of eye, each of which offers a slightly different nuance or shade of meaning.