Ñ is a letter of the extended Latin alphabet, formed by placing a tilde on top of an upper- or lower-case ⟨n⟩. The origin dates back to medieval Spanish, when the Latin digraph ⟨nn⟩ began to be abbreviated using a single ⟨n⟩ with a roughly wavy line above it, and it eventually became part of the Spanish alphabet in the eighteenth century, when it was first formally defined.