zero-derivationhttp://www.oed.com/dictionary/zero-derivation_n%3Ftab%3Dmeaning_and_usezero derivation, n.
Revised 2018

zero derivationnoun

Linguistics.
  1. 1960–
    Derivation in which a word comes to be used with a different grammatical function or (sometimes) in a different (though related) sense from the existing one, without the form of the word being altered.
    Used by those who explain such change in terms of the addition of a ‘zero morpheme’, i.e. derivation by the addition of nothing. The more usual term for this is conversion: see conversion n. II.11e. Compare earlier zero derivative adj.
    1. 1960
      Zero-derivation as a ‘specifically English’ process.
      H. Marchand, Categories Present-day English Word-formation v. 295 (heading)
    2. 1976
      Zero-derivation..must be regarded an extremely productive word-formative process both in English and German, but also in other languages.
      Archivum Linguisticum vol. 7 129
    3. 2011
      Linguists seek to describe and explain a broad range of phenomena, covering territory from acoustic phonetics to zero derivation.
      Times Educational Supplement (Nexis) 3 November (Language & Linguistics section) 17

Originally published as part of the entry for zero, n. & adj.

zero, n. & adj. was revised in June 2018.