you can use setTimeout as follows:
HTML:
<button id="button">message</button>
<div></div>
JavaScript:
$('#button').on('click', function(){
sendMessage();
});
var sended = false ;
function sendMessage(){
if( !sended ){
$('div').html($('div').html() + '<br />new message');
sended = true;
wait( 2000 );
}
}
function wait( miliseconds ){
setTimeout(function(){
sended = false;
}, miliseconds)
}
You can see this working at jsfiddle