Whalest is not a common word and may not have many synonyms that can be used in its place. However, depending on the context in which it is being used, there are some possible alternatives. For instance, if whalest is being used to describe the biggest or largest whale, some synonyms that could be used are colossal, enormous, mammoth, or gigantic. Similarly, if it is being used to describe the most significant or important whale, alternatives could be paramount, supreme, foremost, or preeminent. Nonetheless, it is crucial to consider the context and meaning intended before choosing appropriate synonyms to replace whalest.