Definition of well-formedness in English:

well-formedness

noun

Philosophy Linguistics
  • The fact or condition of being formed according to the rules, especially the syntactic rules, of a language.

Origin

1940s; earliest use found in Journal of Symbolic Logic. From well-formed + -ness.

Pronunciation

well-formedness

/ˌwɛlˈfɔːm(ɪ)dnɪs/