For example , the EncyclopÃ dia Britannica described `` vivisection '' as : `` Operation on a living animal for experimental rather than healing purposes ; more broadly , all experimentation on live animals '' . However , dictionaries note that the wider definition is `` used only by people who are opposed ( dislike ) to such work '' . The term is occasionally used to refer pejoratively to any experiment using living animals ; for example , the EncyclopÃ dia Britannica defines `` vivisection '' as : `` Operation on a living animal for experimental rather than healing purposes ; more broadly , all experimentation on live animals '' , although dictionaries point out that the broader definition is `` used only by people who are opposed to such work '' .