A thin string or twine, or a long thin loaf of bread similar to a baguette.
From French 'ficelle' meaning string or twine, derived from Latin 'filum' (thread), borrowed into English to describe both binding material and bread shapes.
French bakers created such specific bread names that 'ficelle' just means 'string'—because this bread is literally shaped like a thin piece of twine, showing how direct French is!
Complete word intelligence in one call. Free tier — 50 lookups/day.