Crossword clues for One who can't keep a secret. 5 lettersAnswerClueSIEVEOne who can't keep a secret.SIEVEMetaphor for one who's bad at keeping secretsCLAMOne keeping a secret, metaphoricallySTAYUNDERVOC*Keep one's identity secret, sayTREEThe locale of the world's biggest one is kept secret to keep it from being damaged