There are various synonyms that can be used instead of "what a", depending on the context and the intended meaning. Some examples include "so", "such", "very", "incredibly", "utterly", "absolutely", "exceedingly", "remarkably", "terribly", and "unbelievably." For instance, instead of saying "what a beautiful day", you could use "so lovely", "such a nice day", or "incredibly gorgeous weather." Likewise, "what a delicious meal" could be replaced by "absolutely delectable", "utterly scrumptious" or "exceedingly appetizing". Using synonyms can add variety and depth to your language and help to convey a particular tone or emotion more effectively.