When tasked with finding synonyms for the word "gigantical", one realizes its rarity and lack of commonly known alternatives. This indicates that the word itself may be more obscure and less frequently used in everyday language. However, synonyms that convey a similar concept of "immense" or "extremely large" can be identified. Terms such as colossal, gigantic, massive, mammoth, enormous, vast, and humongous all come close to capturing the essence of "gigantical". These alternatives demonstrate the impressive scale or size of an object, giving readers a sense of the immense proportions it possesses. So, when searching for a substitute for "gigantical", one can rely on these words to relay the intended message effectively.