French sauce spoon; saucier spoon
A spoon designed for eating soft fish dishes served in sauce; the term is wasei-eigo, not a direct borrowing of English 'fish spoon'.
wasei-eigo (Japanese-coined English), from fish spoon
In a French course meal, a fish spoon may be provided.
A fish spoon is handy for this white fish covered in plenty of sauce.
Wasei-eigo from English 'fish' and 'spoon', but the meaning is closer to 'French sauce spoon' or 'saucier spoon' rather than a general fish-eating spoon.