We don't have synonyms for seatrout yet — it may be a rare, specialized, newly coined, or misspelled word. The closest thesaurus entries we have are set out, sea trout and eat out.
(n) :
Alternative form of sea trout. [A fish of the species Salmo trutta morpha trutta, closely related to salmon and a subspecies of brown trout. It is lighter in colour than the brown trout, and lives in salt water, returning to fresh water only to spawn.]
(n) :
Alternative form of sea trout. [A fish of the species Salmo trutta morpha trutta, closely related to salmon and a subspecies of brown trout. It is lighter in colour than the brown trout, and lives in salt water, returning to fresh water only to spawn.]