Array Question

Hi, Lets say I have a simple array like this: $myarray = array("a"=>"b","d"=>"c"); echo $myarray[0] will return 'b'; How can I get the name of the index? so: echo $myarray[something] would return 'a'; I know I can do a list($key,$value) but I don't need to loop through the array, I just need to be able to retrieve the key name from any point in the array. Thanks for any help.