a combining form meaning "all," occurring originally in loanwords from Greek ( panacea; panoply ), but now used freely as a general formative ( panleukopenia; panorama; pantelegraph; pantheism; pantonality ), and esp. in terms, formed at will, implying the union of all branches of a group ( Pan-Christian; Panhellenic; Pan-Slavism ). The hyphen and the second capital tend with longer use to be lost, unless they are retained in order to set off clearly the component parts.
Also, pant-, panto- .
[ pan- comb. form of pâs (neut. pân ) all, every, pân everything ]