{n. phr.} Not the only person to be considered; one of many. * /George was acting pretty self-important and we finally had to tell him that he wasn't the only pebble on the beach./ Compare: NOT THE ONLY FISH IN THE SEA.
NOT THE ONLY PEBBLE ON THE BEACH
Meaning of NOT THE ONLY PEBBLE ON THE BEACH in English
Dictionary of English idioms . Словарь английских идиом. 2012