You may try something like this:
var dictionary= {
"My Classes":"My Levels",
"My Class":"My Level",
"college":"university"
};
$("body *").each( function(){
for( var ptrn in dictionary){
$(this).text( $(this).text().replace(new RegExp(ptrn ,"g"), dictionary[ptrn] ) );
}
});
solved Use jQuery to find and replace multiple words on the page [duplicate]