Henry Yule,
Hobson-Jobson — Z
(1903)
“ Zend is the name which has been commonly applied, for more than a hundred years to that dialect of the ancient Iranian (or Persian) language in which the Avesta or Sacred Books of Zorastrianism or the old Persian religion are written. The application of the name in this way was quite erroneous, as the word Zand when used alone in the Parsi books indicates a 'commentary or explanation,' and is in fact applied only to some Pahlavi translation, commentary, or gloss. If the name Zend were now to be used as the designation of any language it would more justly apply to the Pahlavi itself. ”
