best name array indexed id boolean value

i spooky best names arrays variables i use, i'll feeling adult difference thesaurus, dictionary, etc..

so i'm perplexing name array / structure:

$nameme = array(
    '392' => true,
    '234' => true,
    '754' => true,
    '464' => true,
);

and it's used check id certain property, so

if(isset($name[$id])) {
    dosomething();
}

problem being i'm removing unequivocally enlarged non-static names like

$propertynamearrayidindexed

any ideas i improved name sole duty array? improved names general

code1