yes it is possible you can either one or all way what i am gonna suggest below:
1. use unset() function to unset the cookie index and their value
$_COOKIE["TestRookie"]='';
unset($_COOKIE["TestRookie"]);
2. set cookie in very past time , so it become noted as expired cookie
setcookie("TestRookie", "1", time()-3600);
so you can use below code collectively with set cookie in past time and unset it value and key in $_COOKIE
$_COOKIE["TestRookie"]='';
unset($_COOKIE["TestRookie"]);
setcookie("TestRookie", "1", time()-3600);