You understood the meaning of zero moments after you were born. Your birth was followed swiftly by the realization that you had needs. You needed air, you needed food, you needed love. Zero is the number for a lack of things.
Later adults would come to your bed and play peek-a-boo. You would be subjected to seeing a face, and then it would be a blanket, and then a face, and then a blanket again. This game is supposed to teach object-permanence; but before you understood that the person didn’t stop existing when they went behind the blanket, peek-a-boo functioned as a demonstration of “something” and “nothing.” When you saw a face there was something interesting to pay attention to, when the blanket went up it was as if the face had been erased from existence. You understood your first binary opposition. Before “love and hate”, “good and evil”, “true and false”, there was “something and nothing.” As time went on you learned to count the somethings, and then you extended your counting system to “nothing” by including 0.
Later you discovered the true power of zero when you learned to apply it not only to things you were missing, but to anything that was not in existence. The number of crocodiles that your family owned. The number of castles that you lived in. The number of monsters under the bed (though maybe you needed to keep checking for empirical evidence.) Zero allowed your imagination to run wild with possibilities.