Rur. Cliché
very clean. (*Also: as \clean as a whistle.) •After his mother scrubbed him thoroughly, the baby was as clean as a hound's tooth.
•The car was as clean as a whistle after the Girl Scouts washed it.
2.Rur. Cliché
innocent and free from sin or wrong. (*Also: as \clean as a whistle.) •Jane's record was clean as a whistle; she had never committed even the smallest infraction.