We don't have synonyms for seapoy yet — it may be a rare, specialized, newly coined, or misspelled word. The closest thesaurus entries we have are sepoy and teapoy.
(n) :
Alternative form of sepoy. [(historical, military) A native soldier of the East Indies, employed in the service of a European colonial power, notably the British India army (first under the British-chartered East India Company, later in the crown colony), but also France and Portugal.]
(n) :
Alternative form of sepoy. [(historical, military) A native soldier of the East Indies, employed in the service of a European colonial power, notably the British India army (first under the British-chartered East India Company, later in the crown colony), but also France and Portugal.]