May not be earlier but this memo about Flavors in Lisp Machine Lisp from 1980 uses the term Generic Operations: https://dspace.mit.edu/handle/1721.1/5700 https

May not be earlier but this memo about Flavors in Lisp Machine Lisp from 1980 uses the term Generic Operations: https://dspace.mit.edu/handle/1721.1/5700 https://dspace.mit.edu/handle/1721.1/5700 The relevant keyword was called defflavor here, this was later changed to defgeneric in Common Lisp and CLOS.