23(n = noun.quantity) twenty-three, xxiii - the cardinal number that is the sum of twenty-two and one;
is a kind of large integer

   23(s = adj.all) twenty-three, xxiii - being three more than twenty;

   one more than twenty-two; denoting a quantity consisting of twenty-three items or units; -- representing the number twenty-three as Arabic numerals [WordNet 1.5]

atomic number 23, june 23